The development of efficient and real-time marine traffic monitoring systems is becoming increasingly important as maritime activities increase. Automatic Identification System (AIS) is one of the key technologies used to track ship movements, but its utilization is often limited by data accessibility. This research aims to develop a Flask-based API using the Python programming language that is able to provide AIS data quickly and securely. The methods used in this research include API development with RESTful architecture, integration with MongoDB database, and implementation of JSON Web Token (JWT) based authentication mechanism to maintain data access security. This API is integrated with MongoDB database for flexible data storage and support for large scale. The developed API implements a RESTful architecture and is equipped with JWT token-based authentication to maintain data security. Test results show that the API is able to respond to data requests quickly, even under high load. In addition, the authentication and authorization system has been successfully implemented to ensure data security.