diff --git a/paddle/fluid/imperative/basic_engine.cc b/paddle/fluid/imperative/basic_engine.cc
index 94d66c5d080c2763b8928cf6d729251895df393f..9b3c2e510ab1ec0a7d57c972963a041a060c6fce 100644
--- a/paddle/fluid/imperative/basic_engine.cc
+++ b/paddle/fluid/imperative/basic_engine.cc
@@ -215,13 +215,16 @@ void BasicEngine::PrepareGradAccumulators(
 void BasicEngine::PrepareDeps() {
   PADDLE_ENFORCE_EQ(
       node_deps_.empty(), true,
-      platform::errors::AlreadyExists("Op deps must be initialized."));
-  PADDLE_ENFORCE_EQ(
-      accumulators_.empty(), true,
-      platform::errors::AlreadyExists("Accumulators must be initialized."));
-  PADDLE_ENFORCE_EQ(
-      accumulators_with_grad_node_.empty(), true,
-      platform::errors::AlreadyExists("Accumulators must be initialized."));
+      platform::errors::AlreadyExists("Op deps are not empty before preparing "
+                                      "it for backward network execution."));
+  PADDLE_ENFORCE_EQ(accumulators_.empty(), true,
+                    platform::errors::AlreadyExists(
+                        "Accumulators are not empty before preparing it for "
+                        "backward network execution."));
+  PADDLE_ENFORCE_EQ(accumulators_with_grad_node_.empty(), true,
+                    platform::errors::AlreadyExists(
+                        "Accumulators with grad_node as the key are not empty "
+                        "before preparing it for backward network execution."));
 
   std::queue<GradOpNode*> q;
   std::unordered_set<GradOpNode*> visited;
diff --git a/paddle/fluid/imperative/variable_wrapper.h b/paddle/fluid/imperative/variable_wrapper.h
index 5bbabaf3d22d03a0487edfdf09a5470e272a036a..8c7c473c26b5d90b4c972bcdbae407ddf10c73e4 100644
--- a/paddle/fluid/imperative/variable_wrapper.h
+++ b/paddle/fluid/imperative/variable_wrapper.h
@@ -257,11 +257,13 @@ class VariableWrapper {
 
     auto shared_node = grad_node_.lock();
     if (shared_node != grad_node) {
-      PADDLE_ENFORCE_EQ(
-          !shared_node || !grad_node->InplaceGradNameMap().empty(), true,
-          platform::errors::PermissionDenied(
-              "Cannot set gradient op twice unless using Inplace Strategy."));
-      if (shared_node) {
+      if (grad_node->InplaceGradNameMap().empty()) {
+        // grad_node doesn't have Inplace message
+        PADDLE_ENFORCE_EQ(
+            shared_node, nullptr,
+            platform::errors::PermissionDenied(
+                "Cannot set gradient op twice unless using Inplace Strategy."));
+      } else if (shared_node) {
         VLOG(3) << "The gradient op of Var (" << Name()
                 << ") has been set twice. Because Inplace Strategy is used.";
       }