In this system, the key technologies are described in the process of city three dimension electronic map system development. The basic functions are given. Also Marker landmark and Info Window and route guidance are designed The output of the city three dimension map based on 3DMAX is used to combine with baidu powerful electronic map API interface. Some key codes are given to achieve the display view, map zoom, map type switch, information query, bus query, query school, layer management and route query and other functions.