diff --git a/runtime/engine/CMakeLists.txt b/runtime/engine/CMakeLists.txt
index 1032222c3..d64df6489 100644
--- a/runtime/engine/CMakeLists.txt
+++ b/runtime/engine/CMakeLists.txt
@@ -12,7 +12,7 @@ if(WITH_ASR)
 endif()
 
 if(WITH_CLS)
-    add_subdirectory(cls)
+    add_subdirectory(audio_classification)
 endif()
 
 if(WITH_VAD)
diff --git a/runtime/engine/cls/CMakeLists.txt b/runtime/engine/audio_classification/CMakeLists.txt
similarity index 100%
rename from runtime/engine/cls/CMakeLists.txt
rename to runtime/engine/audio_classification/CMakeLists.txt
diff --git a/runtime/engine/cls/nnet/CMakeLists.txt b/runtime/engine/audio_classification/nnet/CMakeLists.txt
similarity index 100%
rename from runtime/engine/cls/nnet/CMakeLists.txt
rename to runtime/engine/audio_classification/nnet/CMakeLists.txt
diff --git a/runtime/engine/cls/nnet/panns_interface.cc b/runtime/engine/audio_classification/nnet/panns_interface.cc
similarity index 95%
rename from runtime/engine/cls/nnet/panns_interface.cc
rename to runtime/engine/audio_classification/nnet/panns_interface.cc
index cfff3f92e..d8b6a8b61 100644
--- a/runtime/engine/cls/nnet/panns_interface.cc
+++ b/runtime/engine/audio_classification/nnet/panns_interface.cc
@@ -12,9 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "cls/nnet/panns_interface.h"
+#include "audio_classification/nnet/panns_interface.h"
 
-#include "cls/nnet/panns_nnet.h"
+#include "audio_classification/nnet/panns_nnet.h"
 #include "common/base/config.h"
 
 namespace ppspeech {
diff --git a/runtime/engine/cls/nnet/panns_interface.h b/runtime/engine/audio_classification/nnet/panns_interface.h
similarity index 100%
rename from runtime/engine/cls/nnet/panns_interface.h
rename to runtime/engine/audio_classification/nnet/panns_interface.h
diff --git a/runtime/engine/cls/nnet/panns_nnet.cc b/runtime/engine/audio_classification/nnet/panns_nnet.cc
similarity index 98%
rename from runtime/engine/cls/nnet/panns_nnet.cc
rename to runtime/engine/audio_classification/nnet/panns_nnet.cc
index 6ab7f7bb6..37ba74f9d 100644
--- a/runtime/engine/cls/nnet/panns_nnet.cc
+++ b/runtime/engine/audio_classification/nnet/panns_nnet.cc
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "cls/nnet/panns_nnet.h"
+#include "audio_classification/nnet/panns_nnet.h"
 #ifdef WITH_PROFILING
 #include "kaldi/base/timer.h"
 #endif
diff --git a/runtime/engine/cls/nnet/panns_nnet.h b/runtime/engine/audio_classification/nnet/panns_nnet.h
similarity index 100%
rename from runtime/engine/cls/nnet/panns_nnet.h
rename to runtime/engine/audio_classification/nnet/panns_nnet.h
diff --git a/runtime/engine/cls/nnet/panns_nnet_main.cc b/runtime/engine/audio_classification/nnet/panns_nnet_main.cc
similarity index 97%
rename from runtime/engine/cls/nnet/panns_nnet_main.cc
rename to runtime/engine/audio_classification/nnet/panns_nnet_main.cc
index 20f3312c9..b47753f0b 100644
--- a/runtime/engine/cls/nnet/panns_nnet_main.cc
+++ b/runtime/engine/audio_classification/nnet/panns_nnet_main.cc
@@ -17,7 +17,7 @@
 
 #include "gflags/gflags.h"
 #include "glog/logging.h"
-#include "cls/nnet/panns_interface.h"
+#include "audio_classification/nnet/panns_interface.h"
 
 DEFINE_string(conf_path, "", "config path");
 DEFINE_string(scp_path, "", "wav scp path");