diff --git a/CMakeLists.txt b/CMakeLists.txt
index 83a48da4d270ad03515e13d9c78450c162719c0b..363bbe0735fe095a333ef10f2a03de232bc25658 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -295,7 +295,6 @@ if(MGE_WITH_TEST)
 endif()
 
 if(MGE_BUILD_IMPERATIVE_RT)
-    add_compile_definitions(MGB_ENABLE_IMPERATIVE_RUNTIME)
     set(CMAKE_CXX_STANDARD 17)
 endif()
 
@@ -711,7 +710,6 @@ endif()
 
 set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${MARCH}")
 
-set(MGB_ENABLE_IMPERATIVE ${MGE_BUILD_IMPERATIVE_RT})
 # Write out megbrain_build_config.h
 # It defines macros needed by both megbrain and dnn
 configure_file(src/megbrain_build_config.h.in ${CMAKE_CURRENT_BINARY_DIR}/genfiles/megbrain_build_config.h)
diff --git a/src/core/impl/graph/cg_impl.h b/src/core/impl/graph/cg_impl.h
index 4f7457dd04b68437849a5ee4c369d51e2c434be9..8c24785f04942fd6451c1491abb3e3468f15a408 100644
--- a/src/core/impl/graph/cg_impl.h
+++ b/src/core/impl/graph/cg_impl.h
@@ -125,9 +125,7 @@ public:
     template<typename T> static ComputingGraphImpl* downcast(T* ptr) = delete;
 
     inline static ComputingGraphImpl* downcast(ComputingGraph* graph) {
-        #ifdef MGB_ENABLE_IMPERATIVE_RUNTIME
         mgb_assert(!graph->options().imperative_proxy_graph);
-        #endif
         return static_cast<ComputingGraphImpl*>(graph);
     }
 
diff --git a/src/megbrain_build_config.h.in b/src/megbrain_build_config.h.in
index 30daf3e310b3acaf677fd71b5d5c02e1d050483c..6caf1c08f80679527b9ee2ef545029ddec81efe1 100644
--- a/src/megbrain_build_config.h.in
+++ b/src/megbrain_build_config.h.in
@@ -34,8 +34,6 @@
 #cmakedefine01 MGB_ENABLE_FBS_SERIALIZATION
 #cmakedefine01 MGB_IS_DEV
 
-#cmakedefine01 MGB_ENABLE_IMPERATIVE
-
 // DNN related flags
 // Platform macro's
 #cmakedefine01 MEGDNN_WITH_CUDA
diff --git a/src/opr/impl/dnn/batch_norm.cpp b/src/opr/impl/dnn/batch_norm.cpp
index 6461573bb38f0043c0774d711eb27d9086f08ba1..52a9c774ab79e802b3f611c99a95048db3eea5cc 100644
--- a/src/opr/impl/dnn/batch_norm.cpp
+++ b/src/opr/impl/dnn/batch_norm.cpp
@@ -140,7 +140,6 @@ void BatchNormForward::scn_do_execute() {
     auto &&y = output(4)->dev_tensor();
     mgb_assert(x.layout().is_contiguous() &&
                y.layout().is_contiguous());
-#if MGB_ENABLE_IMPERATIVE
     if (input().size() == 5) { // need running mean/variance
         auto &&o0 = output(0)->dev_tensor(),
              &&o1 = output(1)->dev_tensor(),
@@ -163,7 +162,6 @@ void BatchNormForward::scn_do_execute() {
                     && o1.raw_ptr() == i1.raw_ptr());
         }
     }
-#endif
     auto scale = input(1)->dev_tensor().as_megdnn();
     auto bias = input(2)->dev_tensor().as_megdnn();
     auto mean = output(0)->dev_tensor().as_megdnn();