diff --git a/launch/description.launch b/launch/description.launch
index f026cf7d9de7f695701b33d6a4bd85bcdcf6450b..2401d6ec77720c75616ae2eb0730c47823f4fe47 100644
--- a/launch/description.launch
+++ b/launch/description.launch
@@ -8,7 +8,7 @@
          command="$(find xacro)/xacro --inorder '$(find iri_ana_description)/urdf/$(arg model).xacro' name:=$(arg node_name)" />
 
   <node pkg="robot_state_publisher" type="state_publisher" name="$(arg node_name)_state_publisher">
-    <param name="tf_prefix" type="string" value="/$arg node_name)"/>
+    <param name="tf_prefix" type="string" value="/$(arg node_name)"/>
     <param name="publish_frequency" type="double" value="20.0"/>
   </node>