The Design and Development of a Handset Game (Castle) Abstract With the rapid development of cell phone business, cell phone games have gradually become the hotspot of mobile value-added services. This graduate design which focuses on J2ME technology designs and develops a handset adventure game (castle). This castle game is a handset RPG game based on J2ME which mainly examines the demon’s collision to touch off the event. It uses midp2.0 technology to achieve the menu, the map, the hero moves, monster AI etc. The game has included the order list, the sound establishment, helps of function etc. Player operates the lead through the handset to collect the stage prop in the castle to break through the labyrinth. The difficulty of the game will gradually increase along with the increase of stage. Otherwise, this intelligence and risk game is filled with enjoyment and the irritating quality witch suits many ages. This paper introduces related technology of the J2ME and the structure analysis and the concrete function realization of this castle game procedure. Key words: J2ME;handset game;castle