diff --git a/doc/fluid/design/muti_devices/kernel_hint_design.md b/doc/fluid/design/muti_devices/kernel_hint_design.md
index 728c8f0b964c02c1efa019945f7427fa879d3aa1..58e44b64169d8c942174de86986403570b271641 100644
--- a/doc/fluid/design/muti_devices/kernel_hint_design.md
+++ b/doc/fluid/design/muti_devices/kernel_hint_design.md
@@ -1,4 +1,6 @@
-# Problem
+# Kernel Hint Design
+
+## Problem
 In PaddlePaddle's [Design](https://github.com/PaddlePaddle/Paddle/blob/develop/doc/design/switch_kernel.md), one Operator may have multiple kernels. Users may have some personal preference to choose a certain type of kernel for an operator, such as `force_cpu` to choose a CPU kernel, `use_cudnn` to choose a CUDNN kernel, we need to provide a way for users to do this.
 
 In the current design, we use KernelType to describe one kernel.
diff --git a/doc/fluid/design/muti_devices/kernel_selection.md b/doc/fluid/design/muti_devices/kernel_selection.md
index 39ea2b00090a864f95610d6d2846ca5e5c904e78..967317d5d2eeb818ab14faabca342cc8c4ed717e 100644
--- a/doc/fluid/design/muti_devices/kernel_selection.md
+++ b/doc/fluid/design/muti_devices/kernel_selection.md
@@ -1,4 +1,6 @@
-# Background
+# Kernel Selection
+
+## Background
 Every operator has many kernels because there are multiple data types, places, data layout, library type that Fluid supports. We use the `OpKernelType ` to describe kernel types that operators can hold.
 
 The `OpKernelType ` is as follows: