diff --git a/changelogs/fragments/4-postgresql_ext.yml b/changelogs/fragments/4-postgresql_ext.yml
new file mode 100644
index 000000000..ddc6a01ea
--- /dev/null
+++ b/changelogs/fragments/4-postgresql_ext.yml
@@ -0,0 +1,2 @@
+minor_changes:
+- postgresql_ext - add the ``comment`` argument (https://github.com/ansible-collections/community.postgresql/issues/354).
diff --git a/plugins/module_utils/postgres.py b/plugins/module_utils/postgres.py
index 42af6323a..714847cee 100644
--- a/plugins/module_utils/postgres.py
+++ b/plugins/module_utils/postgres.py
@@ -541,8 +541,12 @@ def get_comment(cursor, obj_type, obj_name):
     query = ''
     if obj_type == 'role':
         query = ("SELECT pg_catalog.shobj_description(r.oid, 'pg_authid') AS comment "
-                 "FROM pg_catalog.pg_roles r "
+                 "FROM pg_catalog.pg_roles AS r "
                  "WHERE r.rolname = %(obj_name)s")
+    elif obj_type == 'extension':
+        query = ("SELECT pg_catalog.obj_description(e.oid, 'pg_extension') AS comment "
+                 "FROM pg_catalog.pg_extension AS e "
+                 "WHERE e.extname = %(obj_name)s")
 
     cursor.execute(query, {'obj_name': obj_name})
     return cursor.fetchone()['comment']
diff --git a/plugins/modules/postgresql_ext.py b/plugins/modules/postgresql_ext.py
index 7409809f2..2d527e14a 100644
--- a/plugins/modules/postgresql_ext.py
+++ b/plugins/modules/postgresql_ext.py
@@ -88,6 +88,13 @@
     type: bool
     default: true
     version_added: '0.2.0'
+  comment:
+    description:
+    - Sets a comment on the extension.
+    - To reset the comment, pass an empty string.
+    type: str
+    version_added: '3.3.0'
+
 seealso:
 - name: PostgreSQL extensions
   description: General information about PostgreSQL extensions.
@@ -127,6 +134,7 @@
     name: postgis
     db: acme
     schema: foo
+    comment: Test extension
 
 - name: Removes postgis extension to the database acme
   community.postgresql.postgresql_ext:
@@ -191,9 +199,11 @@
 from ansible_collections.community.postgresql.plugins.module_utils.postgres import (
     connect_to_db,
     ensure_required_libs,
+    get_comment,
     get_conn_params,
     pg_cursor_args,
     postgres_common_argument_spec,
+    set_comment,
 )
 
 executed_queries = []
@@ -391,6 +401,7 @@ def main():
         session_role=dict(type="str"),
         version=dict(type="str"),
         trust_input=dict(type="bool", default=True),
+        comment=dict(type="str", default=None),
     )
 
     module = AnsibleModule(
@@ -405,10 +416,12 @@ def main():
     version = module.params["version"]
     session_role = module.params["session_role"]
     trust_input = module.params["trust_input"]
+    comment = module.params["comment"]
+
     changed = False
 
     if not trust_input:
-        check_input(module, ext, schema, version, session_role)
+        check_input(module, ext, schema, version, session_role, comment)
 
     if version and state == 'absent':
         module.warn("Parameter version is ignored when state=absent")
@@ -494,6 +507,12 @@ def main():
                     else:
                         module.fail_json(msg="Extension %s is not available" % ext)
 
+            if comment is not None and comment != get_comment(cursor, 'extension', ext):
+                if module.check_mode:
+                    changed = True
+                else:
+                    changed = set_comment(cursor, comment, 'extension', ext, executed_queries)
+
         elif state == "absent":
             if curr_version:
                 changed = ext_delete(module.check_mode, cursor, ext, cascade)
@@ -524,7 +543,7 @@ def main():
         ext=ext,
         prev_version=out_prev_version,
         version=out_version,
-        queries=executed_queries
+        queries=executed_queries,
     )
 
 
diff --git a/tests/integration/targets/postgresql_ext/tasks/postgresql_ext_initial.yml b/tests/integration/targets/postgresql_ext/tasks/postgresql_ext_initial.yml
index ff79f653b..8f730a367 100644
--- a/tests/integration/targets/postgresql_ext/tasks/postgresql_ext_initial.yml
+++ b/tests/integration/targets/postgresql_ext/tasks/postgresql_ext_initial.yml
@@ -55,13 +55,14 @@
     login_db: postgres
     login_port: 5432
     name: postgis
+    comment: Test comment 1
   ignore_errors: true
   register: result
 
 - assert:
     that:
     - result is changed
-    - result.queries == ['CREATE EXTENSION "postgis"']
+    - result.queries == ['CREATE EXTENSION "postgis"', "COMMENT ON EXTENSION \"postgis\" IS 'Test comment 1'"]
 
 - name: postgresql_ext - check that extension exists after the previous step
   become_user: '{{ pg_user }}'
@@ -76,6 +77,110 @@
     that:
     - result.rowcount == 1
 
+- name: Check the comment
+  become_user: '{{ pg_user }}'
+  become: true
+  postgresql_query:
+    db: postgres
+    query: "SELECT obj_description((SELECT oid FROM pg_catalog.pg_extension WHERE extname = 'postgis'), 'pg_extension') AS comment"
+  register: result
+
+- name: Check the comments match
+  assert:
+    that:
+      - result.query_result[0]['comment'] == "Test comment 1"
+
+
+- name: Now after the comment was set, invoke again not pass the comment explicitly
+  become_user: '{{ pg_user }}'
+  become: true
+  postgresql_ext:
+    login_db: postgres
+    login_port: 5432
+    name: postgis
+  ignore_errors: true
+  register: result
+
+- assert:
+    that:
+    - result is not changed
+    - result.queries == []
+
+- name: Check the comment didn't change
+  become_user: '{{ pg_user }}'
+  become: true
+  postgresql_query:
+    db: postgres
+    query: "SELECT obj_description((SELECT oid FROM pg_catalog.pg_extension WHERE extname = 'postgis'), 'pg_extension') AS comment"
+  register: result
+
+- name: Check the comments match
+  assert:
+    that:
+      - result.query_result[0]['comment'] == "Test comment 1"
+
+
+- name: Reset the comment in check mode
+  become_user: '{{ pg_user }}'
+  become: true
+  postgresql_ext:
+    login_db: postgres
+    login_port: 5432
+    name: postgis
+    comment: ''
+  ignore_errors: true
+  register: result
+  check_mode: true
+
+- assert:
+    that:
+    - result is changed
+    - result.queries == []
+
+- name: Check the comment didn't change
+  become_user: '{{ pg_user }}'
+  become: true
+  postgresql_query:
+    db: postgres
+    query: "SELECT obj_description((SELECT oid FROM pg_catalog.pg_extension WHERE extname = 'postgis'), 'pg_extension') AS comment"
+  register: result
+
+- name: Check the comments match
+  assert:
+    that:
+      - result.query_result[0]['comment'] == "Test comment 1"
+
+
+- name: Reset the comment in real mode
+  become_user: '{{ pg_user }}'
+  become: true
+  postgresql_ext:
+    login_db: postgres
+    login_port: 5432
+    name: postgis
+    comment: ''
+  ignore_errors: true
+  register: result
+
+- assert:
+    that:
+    - result is changed
+    - result.queries == ["COMMENT ON EXTENSION \"postgis\" IS ''"]
+
+- name: Check the comment changed
+  become_user: '{{ pg_user }}'
+  become: true
+  postgresql_query:
+    db: postgres
+    query: "SELECT obj_description((SELECT oid FROM pg_catalog.pg_extension WHERE extname = 'postgis'), 'pg_extension') AS comment"
+  register: result
+
+- name: Check the comments match
+  assert:
+    that:
+      - result.query_result[0]['comment'] == None
+
+
 - name: postgresql_ext - drop extension postgis
   become_user: '{{ pg_user }}'
   become: true