Abstract: This paper develops the third rank natural division Geographic Information System program of highway in east seasonal frost region with MapX，and builds up a data-base on divisional information space．Taking advantage of the function of GIS analyzing，it can manage data and query inform ation efficiently．Make natural factors which affect highway engineering informational and graphic．At the same time，this system can paint various thematic maps in term of demand，and express regional diference dynamically and visually，in order to know the potential efecting caused by nature condition．Put forward sufficient and reliable decision-making for technicians and leaders.

Key words: highway, natural division, third rank division of highway, GIS

摘要： 应用MapX开发了东部温润季冻区公路三级自然区划地理信息系统程序，建立了区划信息空间数据库，运用地理信息系统的空间分析功能，提供高效率的数据管理与信息查询，实现了影响公路工程的自然因素信息化、图形化．系统还可根据需要生成各种专题图，动态、形象地展示了地域间自然因素的分布差异，以了解自然因素对工程的潜在影响，为各部门工程技术人员和管理者提供充分的决策依据．

关键词: 公路, 自然区划, 公路三级区划, 地理信息系统