diff --git a/tests/test_json_response_headers_suite.py b/tests/test_json_response_headers_suite.py
new file mode 100644
index 0000000000..1350dc259a
--- /dev/null
+++ b/tests/test_json_response_headers_suite.py
@@ -0,0 +1,29 @@
+import pytest
+from flask import Flask, jsonify
+
+def test_jsonify_mimetype_and_content_type_invariance():
+    """Verify jsonify sets application/json mimetype and content-type header."""
+    app = Flask(__name__)
+    
+    @app.route("/api/ping")
+    def ping():
+        return jsonify(status="ok", code=200)
+
+    with app.test_client() as client:
+        response = client.get("/api/ping")
+        assert response.status_code == 200
+        assert response.mimetype == "application/json"
+        assert "application/json" in response.headers.get("Content-Type", "")
+        assert response.json == {"status": "ok", "code": 200}
+
+def test_jsonify_empty_dictionary():
+    app = Flask(__name__)
+    
+    @app.route("/api/empty")
+    def empty():
+        return jsonify({})
+
+    with app.test_client() as client:
+        response = client.get("/api/empty")
+        assert response.status_code == 200
+        assert response.json == {}