diff --git a/zetasql/parser/unparser.cc b/zetasql/parser/unparser.cc
index 13ba059c..0eb3cf45 100644
--- a/zetasql/parser/unparser.cc
+++ b/zetasql/parser/unparser.cc
@@ -1373,6 +1373,8 @@ void Unparser::visitASTQuery(const ASTQuery* node, void* data) {
     visitASTChildren(node, data);
   }
   PrintCloseParenIfNeeded(node);
+  // ASTQuery always ends parent.
+  formatter_.FlushCommentsPassedBy(node->parent()->GetParseLocationRange().end(), data);
 }
 
 void Unparser::visitASTSetOperation(const ASTSetOperation* node, void* data) {
diff --git a/zetasql/parser/unparser.h b/zetasql/parser/unparser.h
index 764fdc17..e9641ab9 100644
--- a/zetasql/parser/unparser.h
+++ b/zetasql/parser/unparser.h
@@ -130,7 +130,9 @@ class Unparser : public ParseTreeVisitor {
   }
 
   void visitASTChildren(const ASTNode* node, void* data) {
+    formatter_.FlushCommentsPassedBy(node->GetParseLocationRange().start(), data);
     node->ChildrenAccept(this, data);
+    formatter_.FlushCommentsPassedBy(node->GetParseLocationRange().end(), data);
   }
 
   void visit(const ASTNode* node, void* data) override {