diff --git a/api-openbis-python3-pybis/src/python/pybis/entity_type.py b/api-openbis-python3-pybis/src/python/pybis/entity_type.py
index a17be6eb6b3a05c1d4ed396e581f7be514776655..b752dc666877b583a67ca1f43b56c1f4e6077daa 100644
--- a/api-openbis-python3-pybis/src/python/pybis/entity_type.py
+++ b/api-openbis-python3-pybis/src/python/pybis/entity_type.py
@@ -186,7 +186,10 @@ class EntityType:
         # assign plugin
         if plugin is not None:
             plugin_obj = self.openbis.get_plugin(plugin)
-            new_assignment["plugin"] = plugin_obj.permId
+            new_assignment["pluginId"] = {
+                "@type": 'as.dto.plugin.id.PluginPermId',
+                "permId": plugin_obj.permId
+            }
 
         request = self._get_request_for_pa(new_assignment, "Add")
         try:
diff --git a/api-openbis-python3-pybis/src/python/tests/test_plugin.py b/api-openbis-python3-pybis/src/python/tests/test_plugin.py
index b1707b6cccb555a0706dc5b25ad12211996b7f81..5aa0810be3d6c6b1d0ee4d416814ae826d2dce23 100644
--- a/api-openbis-python3-pybis/src/python/tests/test_plugin.py
+++ b/api-openbis-python3-pybis/src/python/tests/test_plugin.py
@@ -12,13 +12,11 @@
 #   See the License for the specific language governing permissions and
 #   limitations under the License.
 #
-import json
-import re
 
-import pytest
 import time
-from pybis import DataSet
-from pybis import Openbis
+import uuid
+
+import pytest
 
 
 def test_create_delete_plugin(openbis_instance):
@@ -50,6 +48,7 @@ def test_create_delete_plugin(openbis_instance):
         pl_not_exists = openbis_instance.get_plugin(plugin.name)
         assert pl_not_exists is None
 
+
 def test_search_plugins(openbis_instance):
     plugins = openbis_instance.get_plugins(start_with=1, count=1)
     assert len(plugins) == 1
@@ -59,3 +58,59 @@ def test_search_plugins(openbis_instance):
     plugin = plugins[0]
     assert plugin.__class__.__name__ == 'Plugin'
 
+
+def test_assign_plugin_to_sample_type(openbis_instance):
+
+    timestamp = time.strftime("%a_%y%m%d_%H%M%S").upper()
+
+    plugin_name = 'TEST.NEW_PLUGIN_' + timestamp + "_" + str(uuid.uuid4())
+    pl = openbis_instance.new_plugin(
+        name=plugin_name,
+        pluginType='DYNAMIC_PROPERTY',
+        entityKind='SAMPLE',
+        script='def validate(x, True):\n\treturn "OK"'
+    )
+    pl.save()
+
+    sample_type_code = 'SOME_TEST_SAMPLE_TYPE_' + timestamp + "_" + str(uuid.uuid4())
+    sample_type = openbis_instance.new_sample_type(
+        code=sample_type_code,
+        generatedCodePrefix='STST-',
+        autoGeneratedCode=True
+    )
+    sample_type.save()
+
+    sample_type = openbis_instance.get_sample_type(sample_type_code)
+    assignments = sample_type.get_property_assignments().df
+
+    assert len(assignments) == 0
+
+    property_code = 'SOME_TEST_PROPERTY_' + timestamp + "_" + str(uuid.uuid4())
+    prop_type = openbis_instance.new_property_type(
+        code=property_code,
+        label='test property',
+        description='test property',
+        dataType='VARCHAR',
+    )
+    prop_type.save()
+
+    sample_type.assign_property(prop_type, section='General info', ordinal=2,
+                                initialValueForExistingEntities='', plugin=plugin_name)
+
+    assignments = sample_type.get_property_assignments().df
+
+    assert len(assignments) == 1
+    assert assignments.loc[0]['plugin'] == plugin_name
+
+    sample = openbis_instance.new_sample(
+        type=sample_type.code,
+        space='DEFAULT',
+        experiment='/DEFAULT/DEFAULT/DEFAULT',
+        props={property_code.lower(): "some_value"}
+    )
+    sample.save()
+
+    sample_type.revoke_property(property_code, force=True)
+
+    assignments = sample_type.get_property_assignments().df
+    assert len(assignments) == 0