diff --git a/pinot-controller/src/main/java/org/apache/pinot/controller/api/resources/PinotSchemaRestletResource.java b/pinot-controller/src/main/java/org/apache/pinot/controller/api/resources/PinotSchemaRestletResource.java
index d2f997cf61ca..8c85f6d3550e 100644
--- a/pinot-controller/src/main/java/org/apache/pinot/controller/api/resources/PinotSchemaRestletResource.java
+++ b/pinot-controller/src/main/java/org/apache/pinot/controller/api/resources/PinotSchemaRestletResource.java
@@ -392,6 +392,9 @@ private void validateSchemaName(Schema schema) {
       throw new ControllerApplicationException(LOGGER,
           "Invalid schema. Reason: 'schemaName' should not be null or empty", Response.Status.BAD_REQUEST);
     }
+    if (schema.getSchemaName().contains(TableConfig.TABLE_NAME_FORBIDDEN_SUBSTRING)) {
+      throw new IllegalStateException("'schemaName' cannot contain double underscore ('__')");
+    }
   }
 
   private void validateSchemaInternal(Schema schema) {
diff --git a/pinot-spi/src/main/java/org/apache/pinot/spi/config/table/TableConfig.java b/pinot-spi/src/main/java/org/apache/pinot/spi/config/table/TableConfig.java
index e5e11b0bd984..7eba79f6d89a 100644
--- a/pinot-spi/src/main/java/org/apache/pinot/spi/config/table/TableConfig.java
+++ b/pinot-spi/src/main/java/org/apache/pinot/spi/config/table/TableConfig.java
@@ -60,7 +60,7 @@ public class TableConfig extends BaseJsonConfig {
   public static final String TIER_OVERWRITES_KEY = "tierOverwrites";
 
   // Double underscore is reserved for real-time segment name delimiter
-  private static final String TABLE_NAME_FORBIDDEN_SUBSTRING = "__";
+  public static final String TABLE_NAME_FORBIDDEN_SUBSTRING = "__";
 
   /* MANDATORY FIELDS */