diff --git a/invenio_vocabularies/contrib/names/schema.py b/invenio_vocabularies/contrib/names/schema.py
index 380bd7fd..287d4f86 100644
--- a/invenio_vocabularies/contrib/names/schema.py
+++ b/invenio_vocabularies/contrib/names/schema.py
@@ -56,6 +56,20 @@ def validate_names(self, data, **kwargs):
             ]
             raise ValidationError({"family_name": messages})
 
+    @validates_schema
+    def validate_affiliatons(self, data, **kwargs):
+        """Validate names."""
+        affiliations = data.get("affiliations", [])
+        seen_names = set()
+        for affiliation in affiliations:
+            name = affiliation.get("name")
+            if not affiliation.get("id") and name:
+                if name in seen_names:
+                    messages = [_("Duplicated affiliations.")]
+                    raise ValidationError({"affiliations": messages})
+                else:
+                    seen_names.add(name)
+
     @post_load
     def update_name(self, data, **kwargs):
         """Update names for person.
diff --git a/tests/contrib/names/test_names_schema.py b/tests/contrib/names/test_names_schema.py
index fea19d62..dd1bb37c 100644
--- a/tests/contrib/names/test_names_schema.py
+++ b/tests/contrib/names/test_names_schema.py
@@ -66,3 +66,19 @@ def test_invalid_no_names(app):
 
     with pytest.raises(ValidationError):
         data = NameSchema().load(invalid)
+
+
+def test_duplicated_affiliations(app):
+    invalid = {
+        "family_name": "Doe",
+        "given_name": "John",
+        "name": "Doe, John",
+        "id": "0000-0001-8135-3489",
+        "identifiers": [{"identifier": "0000-0001-8135-3489", "scheme": "orcid"}],
+        "affiliations": [{"name": "CustomORG"}, {"name": "CustomORG"}],
+    }
+    with pytest.raises(ValidationError) as e:
+        NameSchema().load(invalid)
+
+    messages = e.value.normalized_messages()
+    assert {"affiliations": ["Duplicated affiliations."]} == messages