diff --git a/app/config.py b/app/config.py
index 8637bcdd6..f67bfaeaf 100644
--- a/app/config.py
+++ b/app/config.py
@@ -243,6 +243,12 @@ def MFA_API_URI(self) -> str:  # noqa: N802
             return "https://api.multifactor.dev"
         return "https://api.multifactor.ru"
 
+    @computed_field  # type: ignore
+    @cached_property
+    def is_global_catalog(self) -> bool:
+        """Check if this is Global Catalog server."""
+        return self.PORT in (self.GLOBAL_LDAP_PORT, self.GLOBAL_LDAP_TLS_PORT)
+
     @computed_field  # type: ignore
     @cached_property
     def KRB5_CONFIG_SERVER(self) -> HttpUrl:  # noqa: N802
diff --git a/app/ldap_protocol/ldap_requests/search.py b/app/ldap_protocol/ldap_requests/search.py
index d5ff4e679..b82e41ff7 100644
--- a/app/ldap_protocol/ldap_requests/search.py
+++ b/app/ldap_protocol/ldap_requests/search.py
@@ -304,9 +304,16 @@ async def get_result(
                 result_code=LDAPCodes.INSUFFICIENT_ACCESS_RIGHTS,
             )
             return
+        base_directories = await get_base_directories(ctx.session)
+        if (
+            ctx.settings.is_global_catalog
+            and not self.base_object
+            and base_directories
+        ):
+            self.base_object = base_directories[0].path_dn
 
         query = self._build_query(
-            await get_base_directories(ctx.session),
+            base_directories,
             user,
             ctx.access_manager,
         )