Automatic Identification System (AIS) is recently introduced to the maritime navigation systems. It is aimed to increase safety of vessels at sea by exchanging information to coastal monitoring stations. This article presents a ship traffic monitoring system by using the AIS information communication system using MS Visual C++. Then, the mobile Internet AIS introduced here is considerably improving and extending AIS functionalities compared to VHF AIS. When each ship is connected to the Internet network through the developed AIS system with her own client ID, all of her AIS information is surely sent to a server at her own base station by processing the information via the Internet network.