diff --git a/dakara_server/library/serializers.py b/dakara_server/library/serializers.py
index 03e70e8b..4a1a02b2 100644
--- a/dakara_server/library/serializers.py
+++ b/dakara_server/library/serializers.py
@@ -115,7 +115,7 @@ class WorkTypeSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = WorkType
-        fields = ("name", "name_plural", "query_name", "icon_name")
+        fields = ("id", "name", "name_plural", "query_name", "icon_name")
 
     @staticmethod
     def set(work_type_data):
@@ -144,7 +144,7 @@ class WorkTypeForWorkSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = WorkType
-        fields = ("name", "name_plural", "query_name", "icon_name")
+        fields = ("id", "name", "name_plural", "query_name", "icon_name")
         extra_kwargs = {
             "name": {"required": False},
             "name_plural": {"required": False},
diff --git a/dakara_server/library/tests/base_test.py b/dakara_server/library/tests/base_test.py
index b12d2121..49596682 100644
--- a/dakara_server/library/tests/base_test.py
+++ b/dakara_server/library/tests/base_test.py
@@ -131,6 +131,7 @@ def check_work_json(self, json, expected_work):
 
     def check_work_type_json(self, json, expected_work_type):
         """Method to test an representation against the expected work type."""
+        self.assertEqual(json["id"], expected_work_type.id)
         self.assertEqual(json["name"], expected_work_type.name)
         self.assertEqual(json["name_plural"], expected_work_type.name_plural)
         self.assertEqual(json["query_name"], expected_work_type.query_name)