diff --git a/sqlglot/expressions.py b/sqlglot/expressions.py
index b70a521ced..f8459a173f 100644
--- a/sqlglot/expressions.py
+++ b/sqlglot/expressions.py
@@ -8317,6 +8317,9 @@ def merge(
     if returning:
         merge = merge.returning(returning, dialect=dialect, copy=False, **opts)
 
+    if isinstance(using_clause := merge.args.get("using"), Alias):
+        using_clause.replace(alias_(using_clause.this, using_clause.args["alias"], table=True))
+
     return merge
 
 
diff --git a/tests/dialects/test_oracle.py b/tests/dialects/test_oracle.py
index bcbe8e523e..fc1002ce0b 100644
--- a/tests/dialects/test_oracle.py
+++ b/tests/dialects/test_oracle.py
@@ -777,3 +777,17 @@ def test_utc_time(self):
         self.validate_identity("UTC_TIME(6)").assert_is(exp.UtcTime)
         self.validate_identity("UTC_TIMESTAMP()").assert_is(exp.UtcTimestamp)
         self.validate_identity("UTC_TIMESTAMP(6)").assert_is(exp.UtcTimestamp)
+
+    def test_merge_builder_alias(self):
+        merge_stmt = exp.merge(
+            "WHEN MATCHED THEN UPDATE SET my_table.col1 = source_table.col1",
+            "WHEN NOT MATCHED THEN INSERT (my_table.id, my_table.col1) VALUES (source_table.id, source_table.col1)",
+            into="my_table",
+            using="(SELECT * FROM something) source_table",
+            on="my_table.id = source_table.id",
+            dialect="oracle",
+        )
+        self.assertEqual(
+            merge_stmt.sql("oracle"),
+            "MERGE INTO my_table USING (SELECT * FROM something) source_table ON my_table.id = source_table.id WHEN MATCHED THEN UPDATE SET my_table.col1 = source_table.col1 WHEN NOT MATCHED THEN INSERT (my_table.id, my_table.col1) VALUES (source_table.id, source_table.col1)",
+        )