diff --git a/services/src/main/java/org/apache/druid/cli/CliCoordinator.java b/services/src/main/java/org/apache/druid/cli/CliCoordinator.java
index c1ab5b94a7dc..98bb958d9c50 100644
--- a/services/src/main/java/org/apache/druid/cli/CliCoordinator.java
+++ b/services/src/main/java/org/apache/druid/cli/CliCoordinator.java
@@ -272,10 +272,12 @@ public LoadQueueTaskMaster getLoadQueueTaskMaster(
         }
     );
 
-    modules.add(new LookupSerdeModule());
-
     if (beOverlord) {
       modules.addAll(new CliOverlord().getModules(false));
+    } else {
+      // Only add LookupSerdeModule if !beOverlord, since CliOverlord includes it, and having two copies causes
+      // the injector to get confused due to having multiple bindings for the same classes.
+      modules.add(new LookupSerdeModule());
     }
 
     return modules;