diff --git a/dialogflow_task_executive/CMakeLists.txt b/dialogflow_task_executive/CMakeLists.txt
index 5e66b261a..9db855ef9 100644
--- a/dialogflow_task_executive/CMakeLists.txt
+++ b/dialogflow_task_executive/CMakeLists.txt
@@ -71,7 +71,7 @@ elseif("$ENV{ROS_DISTRO}" STRGREATER "melodic")
 else()
   catkin_generate_virtualenv(
     INPUT_REQUIREMENTS requirements.in
-    PYTHON_INTERPRETER python2
+    PYTHON_INTERPRETER python3
     )
 endif()
 
diff --git a/dialogflow_task_executive/node_scripts/dialogflow_client.py b/dialogflow_task_executive/node_scripts/dialogflow_client.py
index cb4253243..df562c9b7 100644
--- a/dialogflow_task_executive/node_scripts/dialogflow_client.py
+++ b/dialogflow_task_executive/node_scripts/dialogflow_client.py
@@ -117,7 +117,7 @@ def make_dialog_msg(self, result):
         # check if ROS_PYTHON_VERSION exists in indigo
         if (self.language == 'ja-JP'
             and ("ROS_PYTHON_VERSION" not in os.environ
-                 or os.environ["ROS_PYTHON_VERSION"] == "2")):
+                 or sys.version_info.major <= 2)):
             msg.query = result.query_text.encode("utf-8")
             msg.response = result.fulfillment_text.encode("utf-8")
         else: