diff --git a/ppdet/modeling/backbones/__init__.py b/ppdet/modeling/backbones/__init__.py
index fe52f12bb6a0cae5d6b7df94451926bb01f859d9..12e9354b744dc97e2de584915a8827d137a3f7c2 100644
--- a/ppdet/modeling/backbones/__init__.py
+++ b/ppdet/modeling/backbones/__init__.py
@@ -33,6 +33,7 @@ from . import cspresnet
 from . import csp_darknet
 from . import convnext
 from . import vision_transformer
+from . import mobileone
 
 from .vgg import *
 from .resnet import *
@@ -54,4 +55,6 @@ from .esnet import *
 from .cspresnet import *
 from .csp_darknet import *
 from .convnext import *
-from .vision_transformer import *
\ No newline at end of file
+from .vision_transformer import *
+from .vision_transformer import *
+from .mobileone import *
diff --git a/ppdet/modeling/backbones/mobileone.py b/ppdet/modeling/backbones/mobileone.py
new file mode 100644
index 0000000000000000000000000000000000000000..64aa32726132ab7387dca725dee0f4bc029fad8e
--- /dev/null
+++ b/ppdet/modeling/backbones/mobileone.py
@@ -0,0 +1,265 @@
+# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+This code is the paddle implementation of MobileOne block, see: https://arxiv.org/pdf/2206.04040.pdf. 
+Some codes are based on https://github.com/DingXiaoH/RepVGG/blob/main/repvgg.py
+Ths copyright of microsoft/Swin-Transformer is as follows:
+MIT License [see LICENSE for details]
+"""
+
+import paddle
+import paddle.nn as nn
+from paddle import ParamAttr
+from paddle.regularizer import L2Decay
+from paddle.nn.initializer import Normal
+
+from ppdet.modeling.ops import get_act_fn
+from ppdet.modeling.layers import ConvNormLayer
+
+
+class MobileOneBlock(nn.Layer):
+    def __init__(
+            self,
+            ch_in,
+            ch_out,
+            stride,
+            kernel_size,
+            conv_num=1,
+            norm_type='bn',
+            norm_decay=0.,
+            norm_groups=32,
+            bias_on=False,
+            lr_scale=1.,
+            freeze_norm=False,
+            initializer=Normal(
+                mean=0., std=0.01),
+            skip_quant=False,
+            act='relu', ):
+        super(MobileOneBlock, self).__init__()
+
+        self.ch_in = ch_in
+        self.ch_out = ch_out
+        self.kernel_size = kernel_size
+        self.stride = stride
+        self.padding = (kernel_size - 1) // 2
+        self.k = conv_num
+
+        self.depth_conv = nn.LayerList()
+        self.point_conv = nn.LayerList()
+        for i in range(self.k):
+            if i > 0:
+                stride = 1
+            self.depth_conv.append(
+                ConvNormLayer(
+                    ch_in,
+                    ch_in,
+                    kernel_size,
+                    stride=stride,
+                    groups=ch_in,
+                    norm_type=norm_type,
+                    norm_decay=norm_decay,
+                    norm_groups=norm_groups,
+                    bias_on=bias_on,
+                    lr_scale=lr_scale,
+                    freeze_norm=freeze_norm,
+                    initializer=initializer,
+                    skip_quant=skip_quant))
+            self.point_conv.append(
+                ConvNormLayer(
+                    ch_in,
+                    ch_out,
+                    1,
+                    stride=1,
+                    groups=1,
+                    norm_type=norm_type,
+                    norm_decay=norm_decay,
+                    norm_groups=norm_groups,
+                    bias_on=bias_on,
+                    lr_scale=lr_scale,
+                    freeze_norm=freeze_norm,
+                    initializer=initializer,
+                    skip_quant=skip_quant))
+        self.rbr_1x1 = ConvNormLayer(
+            ch_in,
+            ch_in,
+            1,
+            stride=self.stride,
+            groups=ch_in,
+            norm_type=norm_type,
+            norm_decay=norm_decay,
+            norm_groups=norm_groups,
+            bias_on=bias_on,
+            lr_scale=lr_scale,
+            freeze_norm=freeze_norm,
+            initializer=initializer,
+            skip_quant=skip_quant)
+        self.rbr_identity_st1 = nn.BatchNorm2D(
+            num_features=ch_in,
+            weight_attr=ParamAttr(regularizer=L2Decay(0.0)),
+            bias_attr=ParamAttr(regularizer=L2Decay(
+                0.0))) if ch_in == ch_out and self.stride == 1 else None
+        self.rbr_identity_st2 = nn.BatchNorm2D(
+            num_features=ch_out,
+            weight_attr=ParamAttr(regularizer=L2Decay(0.0)),
+            bias_attr=ParamAttr(regularizer=L2Decay(0.0)))
+        self.act = get_act_fn(act) if act is None or isinstance(act, (
+            str, dict)) else act
+
+    def forward(self, x):
+        if hasattr(self, "conv1") and hasattr(self, "conv2"):
+            y = self.act(self.conv2(self.act(self.conv1(x))))
+        else:
+            if self.rbr_identity_st1 is None:
+                id_out_st1 = 0
+            else:
+                id_out_st1 = self.rbr_identity_st1(x)
+
+            x1_1 = x.clone()
+            for i in range(self.k):
+                x1_1 = self.depth_conv[i](x1_1)
+            x1_2 = self.rbr_1x1(x)
+            x1 = self.act(x1_1 + x1_2 + id_out_st1)
+
+            if self.rbr_identity_st2 is None:
+                id_out_st2 = 0
+            else:
+                id_out_st2 = self.rbr_identity_st2(x1)
+
+            x2_1 = x1.clone()
+            for i in range(self.k):
+                x2_1 = self.point_conv[i](x2_1)
+            y = self.act(x2_1 + id_out_st2)
+
+        return y
+
+    def convert_to_deploy(self):
+        if not hasattr(self, 'conv1'):
+            self.conv1 = nn.Conv2D(
+                in_channels=self.ch_in,
+                out_channels=self.ch_in,
+                kernel_size=self.kernel_size,
+                stride=self.stride,
+                padding=self.padding,
+                groups=self.ch_in)
+        if not hasattr(self, 'conv2'):
+            self.conv2 = nn.Conv2D(
+                in_channels=self.ch_in,
+                out_channels=self.ch_out,
+                kernel_size=1,
+                stride=1,
+                padding='SAME',
+                groups=1)
+
+        conv1_kernel, conv1_bias, conv2_kernel, conv2_bias = self.get_equivalent_kernel_bias(
+        )
+        self.conv1.weight.set_value(conv1_kernel)
+        self.conv1.bias.set_value(conv1_bias)
+        self.conv2.weight.set_value(conv2_kernel)
+        self.conv2.bias.set_value(conv2_bias)
+        self.__delattr__('depth_conv')
+        self.__delattr__('point_conv')
+        self.__delattr__('rbr_1x1')
+        if hasattr(self, 'rbr_identity_st1'):
+            self.__delattr__('rbr_identity_st1')
+        if hasattr(self, 'rbr_identity_st2'):
+            self.__delattr__('rbr_identity_st2')
+        if hasattr(self, 'id_tensor'):
+            self.__delattr__('id_tensor')
+
+    def get_equivalent_kernel_bias(self):
+        st1_kernel3x3, st1_bias3x3 = self._fuse_bn_tensor(self.depth_conv)
+        st1_kernel1x1, st1_bias1x1 = self._fuse_bn_tensor(self.rbr_1x1)
+        st1_kernelid, st1_biasid = self._fuse_bn_tensor(
+            self.rbr_identity_st1, kernel_size=self.kernel_size)
+
+        st2_kernel1x1, st2_bias1x1 = self._fuse_bn_tensor(self.point_conv)
+        st2_kernelid, st2_biasid = self._fuse_bn_tensor(
+            self.rbr_identity_st2, kernel_size=1)
+
+        conv1_kernel = st1_kernel3x3 + self._pad_1x1_to_3x3_tensor(
+            st1_kernel1x1) + st1_kernelid
+
+        conv1_bias = st1_bias3x3 + st1_bias1x1 + st1_biasid
+
+        conv2_kernel = st2_kernel1x1 + st2_kernelid
+        conv2_bias = st2_bias1x1 + st2_biasid
+
+        return conv1_kernel, conv1_bias, conv2_kernel, conv2_bias
+
+    def _pad_1x1_to_3x3_tensor(self, kernel1x1):
+        if kernel1x1 is None:
+            return 0
+        else:
+            padding_size = (self.kernel_size - 1) // 2
+            return nn.functional.pad(
+                kernel1x1,
+                [padding_size, padding_size, padding_size, padding_size])
+
+    def _fuse_bn_tensor(self, branch, kernel_size=3):
+        if branch is None:
+            return 0, 0
+
+        if isinstance(branch, nn.LayerList):
+            kernel = 0
+            running_mean = 0
+            running_var = 0
+            gamma = 0
+            beta = 0
+            eps = 0
+            for block in branch:
+                kernel += block.conv.weight
+                running_mean += block.norm._mean
+                running_var += block.norm._variance
+                gamma += block.norm.weight
+                beta += block.norm.bias
+                eps += block.norm._epsilon
+
+            kernel /= len(branch)
+            running_mean /= len(branch)
+            running_var /= len(branch)
+            gamma /= len(branch)
+            beta /= len(branch)
+            eps /= len(branch)
+        elif isinstance(branch, ConvNormLayer):
+            kernel = branch.conv.weight
+            running_mean = branch.norm._mean
+            running_var = branch.norm._variance
+            gamma = branch.norm.weight
+            beta = branch.norm.bias
+            eps = branch.norm._epsilon
+        else:
+            assert isinstance(branch, nn.BatchNorm2D)
+            input_dim = self.ch_in if kernel_size == 1 else 1
+            kernel_value = paddle.zeros(
+                shape=[self.ch_in, input_dim, kernel_size, kernel_size],
+                dtype='float32')
+            if kernel_size > 1:
+                for i in range(self.ch_in):
+                    kernel_value[i, i % input_dim, 1, 1] = 1
+            elif kernel_size == 1:
+                for i in range(self.ch_in):
+                    kernel_value[i, i % input_dim, 0, 0] = 1
+            else:
+                raise ValueError("Invalid kernel size recieved!")
+            kernel = paddle.to_tensor(kernel_value, place=branch.weight.place)
+            running_mean = branch._mean
+            running_var = branch._variance
+            gamma = branch.weight
+            beta = branch.bias
+            eps = branch._epsilon
+
+        std = (running_var + eps).sqrt()
+        t = (gamma / std).reshape((-1, 1, 1, 1))
+
+        return kernel * t, beta - running_mean * gamma / std
diff --git a/ppdet/modeling/losses/iou_loss.py b/ppdet/modeling/losses/iou_loss.py
index 9b8da6c059c90d7bbba7b8e5688aa7556a38ac63..b5cac22e342e633b5c413805623ba4015073b3b1 100644
--- a/ppdet/modeling/losses/iou_loss.py
+++ b/ppdet/modeling/losses/iou_loss.py
@@ -17,13 +17,13 @@ from __future__ import division
 from __future__ import print_function
 
 import numpy as np
-
+import math
 import paddle
 
 from ppdet.core.workspace import register, serializable
 from ..bbox_utils import bbox_iou
 
-__all__ = ['IouLoss', 'GIoULoss', 'DIouLoss']
+__all__ = ['IouLoss', 'GIoULoss', 'DIouLoss', 'SIoULoss']
 
 
 @register
@@ -208,3 +208,88 @@ class DIouLoss(GIoULoss):
         diou = paddle.mean((1 - iouk + ciou_term + diou_term) * iou_weight)
 
         return diou * self.loss_weight
+
+
+@register
+@serializable
+class SIoULoss(GIoULoss):
+    """
+    see https://arxiv.org/pdf/2205.12740.pdf 
+    Args:
+        loss_weight (float): siou loss weight, default as 1
+        eps (float): epsilon to avoid divide by zero, default as 1e-10
+        theta (float): default as 4
+        reduction (str): Options are "none", "mean" and "sum". default as none
+    """
+
+    def __init__(self, loss_weight=1., eps=1e-10, theta=4., reduction='none'):
+        super(SIoULoss, self).__init__(loss_weight=loss_weight, eps=eps)
+        self.loss_weight = loss_weight
+        self.eps = eps
+        self.theta = theta
+        self.reduction = reduction
+
+    def __call__(self, pbox, gbox):
+        x1, y1, x2, y2 = paddle.split(pbox, num_or_sections=4, axis=-1)
+        x1g, y1g, x2g, y2g = paddle.split(gbox, num_or_sections=4, axis=-1)
+
+        box1 = [x1, y1, x2, y2]
+        box2 = [x1g, y1g, x2g, y2g]
+        iou = bbox_iou(box1, box2)
+
+        cx = (x1 + x2) / 2
+        cy = (y1 + y2) / 2
+        w = x2 - x1 + self.eps
+        h = y2 - y1 + self.eps
+
+        cxg = (x1g + x2g) / 2
+        cyg = (y1g + y2g) / 2
+        wg = x2g - x1g + self.eps
+        hg = y2g - y1g + self.eps
+
+        x2 = paddle.maximum(x1, x2)
+        y2 = paddle.maximum(y1, y2)
+
+        # A or B
+        xc1 = paddle.minimum(x1, x1g)
+        yc1 = paddle.minimum(y1, y1g)
+        xc2 = paddle.maximum(x2, x2g)
+        yc2 = paddle.maximum(y2, y2g)
+
+        cw_out = xc2 - xc1
+        ch_out = yc2 - yc1
+
+        ch = paddle.maximum(cy, cyg) - paddle.minimum(cy, cyg)
+        cw = paddle.maximum(cx, cxg) - paddle.minimum(cx, cxg)
+
+        # angle cost
+        dist_intersection = paddle.sqrt((cx - cxg)**2 + (cy - cyg)**2)
+        sin_angle_alpha = ch / dist_intersection
+        sin_angle_beta = cw / dist_intersection
+        thred = paddle.pow(paddle.to_tensor(2), 0.5) / 2
+        thred.stop_gradient = True
+        sin_alpha = paddle.where(sin_angle_alpha > thred, sin_angle_beta,
+                                 sin_angle_alpha)
+        angle_cost = paddle.cos(paddle.asin(sin_alpha) * 2 - math.pi / 2)
+
+        # distance cost
+        gamma = 2 - angle_cost
+        # gamma.stop_gradient = True
+        beta_x = ((cxg - cx) / cw_out)**2
+        beta_y = ((cyg - cy) / ch_out)**2
+        dist_cost = 1 - paddle.exp(-gamma * beta_x) + 1 - paddle.exp(-gamma *
+                                                                     beta_y)
+
+        # shape cost
+        omega_w = paddle.abs(w - wg) / paddle.maximum(w, wg)
+        omega_h = paddle.abs(hg - h) / paddle.maximum(h, hg)
+        omega = (1 - paddle.exp(-omega_w))**self.theta + (
+            1 - paddle.exp(-omega_h))**self.theta
+        siou_loss = 1 - iou + (omega + dist_cost) / 2
+
+        if self.reduction == 'mean':
+            siou_loss = paddle.mean(siou_loss)
+        elif self.reduction == 'sum':
+            siou_loss = paddle.sum(siou_loss)
+
+        return siou_loss * self.loss_weight