diff --git a/core/predictor/common/constant.h b/core/predictor/common/constant.h
index dd4c5733c410864f3bf8449891bd90e1aec457b1..ec0c5b4ee292f840b6fd8638b891f9d341463dd5 100644
--- a/core/predictor/common/constant.h
+++ b/core/predictor/common/constant.h
@@ -43,8 +43,6 @@ DECLARE_bool(enable_model_toolkit);
 DECLARE_string(enable_protocol_list);
 DECLARE_bool(enable_cube);
 DECLARE_bool(enable_general_model);
-DECLARE_string(precision);
-DECLARE_bool(use_calib);
 
 // STATIC Variables
 extern const char* START_OP_NAME;
diff --git a/core/predictor/common/utils.h b/core/predictor/common/utils.h
index 6108389bbbfa5609fc12ee39381906e50ad0b847..7fee442d43a2e9344150647ddba16e91c24a3044 100644
--- a/core/predictor/common/utils.h
+++ b/core/predictor/common/utils.h
@@ -29,21 +29,22 @@ namespace butil = base;
 #endif
 
 enum class Precision {
-  kFloat32 = 0,  ///< fp32
-  kInt8,         ///< int8
-  kHalf,         ///< fp16
-  kBfloat16,     ///< bf16
+  kUnk = -1,     // unknown type
+  kFloat32 = 0,  // fp32
+  kInt8,         // int8
+  kHalf,         // fp16
+  kBfloat16      // bf16
 };
 
-string PrecisionTypeString(const Precision data_type) {
+std::string PrecisionTypeString(const Precision data_type) {
   switch (data_type) {
-    case 0:
+    case Precision::kFloat32:
       return "kFloat32";
-    case 1:
+    case Precision::kInt8:
       return "kInt8";
-    case 2:
+    case Precision::kHalf:
       return "kHalf";
-    case 3:
+    case Precision::kBfloat16:
       return "kBloat16";
     default:
       return "unUnk";
@@ -59,20 +60,6 @@ std::string ToLower(const std::string& data) {
   return result;
 }
 
-Precision GetPrecision(const std::string& precision_data) {
-  std::string precision_type = ToLower(precision_data);
-  if (precision_type == "fp32") {
-    return Precision::kFloat32;
-  } else if (precision_type == "int8") {
-    return Precison::kInt8;
-  } else if (precision_type == "fp16") {
-    return Precision::kHalf;
-  } else if (precision_type == "bf16") {
-    return Precision::kBfloat16;
-  }
-  return "unknow type";
-}
-
 class TimerFlow {
  public:
   static const int MAX_SIZE = 1024;
diff --git a/paddle_inference/paddle/include/paddle_engine.h b/paddle_inference/paddle/include/paddle_engine.h
index 10bcdbfd7a075016649a3b986be2d777f3fbe3a8..a2be5257aeedb984a9d30b9946c707fcf3ff824d 100644
--- a/paddle_inference/paddle/include/paddle_engine.h
+++ b/paddle_inference/paddle/include/paddle_engine.h
@@ -37,10 +37,24 @@ using paddle_infer::Tensor;
 using paddle_infer::CreatePredictor;
 
 DECLARE_int32(gpuid);
+DECLARE_string(precision);
+DECLARE_bool(use_calib);
 
 static const int max_batch = 32;
 static const int min_subgraph_size = 3;
-static predictor::Precision precision_type;
+static PrecisionType precision_type;
+
+PrecisionType GetPrecision(const std::string& precision_data) {
+  std::string precision_type = predictor::ToLower(precision_data);
+  if (precision_type == "fp32") {
+    return PrecisionType::kFloat32;
+  } else if (precision_type == "int8") {
+    return PrecisionType::kInt8;
+  } else if (precision_type == "fp16") {
+    return PrecisionType::kHalf;
+  }
+  return PrecisionType::kFloat32;
+}
 
 // Engine Base
 class PaddleEngineBase {
@@ -138,7 +152,7 @@ class PaddleInferenceEngine : public PaddleEngineBase {
       // 2000MB GPU memory
       config.EnableUseGpu(2000, FLAGS_gpuid);
     }
-    precision_type = predictor::GetPrecision(FLAGS_precision);
+    precision_type = GetPrecision(FLAGS_precision);
 
     if (engine_conf.has_use_trt() && engine_conf.use_trt()) {
       if (!engine_conf.has_use_gpu() || !engine_conf.use_gpu()) {
@@ -149,7 +163,7 @@ class PaddleInferenceEngine : public PaddleEngineBase {
                                   min_subgraph_size,
                                   precision_type,
                                   false,
-                                  use_calib);
+                                  FLAGS_use_calib);
       LOG(INFO) << "create TensorRT predictor";
     }
 
@@ -160,9 +174,9 @@ class PaddleInferenceEngine : public PaddleEngineBase {
     if ((!engine_conf.has_use_lite() && !engine_conf.has_use_gpu()) ||
         (engine_conf.has_use_lite() && !engine_conf.use_lite() &&
          engine_conf.has_use_gpu() && !engine_conf.use_gpu())) {
-      if (precision_type == Precision::kInt8) {
+      if (precision_type == PrecisionType::kInt8) {
         config.EnableMkldnnQuantizer();
-      } else if (precision_type == Precision::kHalf) {
+      } else if (precision_type == PrecisionType::kHalf) {
         config.EnableMkldnnBfloat16();
       }
     }