CGCS2000是目前最新的国家大地坐标系，具有高精度、地心、动态、统一等特点，为国家各项社会经济活动提供了基础性保障。宜昌城区在长时间的发展过程中，不同部门分别于不同时期形成了基于1954北京坐标系、1980西安坐标系、CGCS2000等多种坐标系的基础地理信息数据，不利于数据的共享使用。鉴于此，首先介绍了宜昌城区2000国家大地基准的建设情况；然后确立了不同坐标系之间转换关系，研制了数据坐标转换软件，检核了转换参数的精度；最终建立了符合宜昌城区的最优坐标系转换方案，为宜昌城区不同坐标系基础地理信息数据的整合、统一提供了参数和软件基础。

CGCS2000 is the latest national geodetic coordinate system. It has the characteristics of high precision, geocentricity, dynamics and unity, and can provide a basic guarantee for various social and economic activities of the country. In the long-term development process of Yichang City, different departments have formed basic geographical information data based on 1954 Beijing coordinate system, 1980 Xi'an coordinate system, CGCS2000 and other coordinate systems, which is not conducive to the sharing and use of data. In view of the above problems,we introduced the construction of 2000 national geodetic datum in Yichang urban area at first. Then, we established the conversion relationship between different coordinate systems, developed the data coordinate conversion software, and checked the accuracy of conversion parameters. Finally, we established the optimal coordinate system transformation scheme in Yichang City, which could provide parameters and software basis for the integration and unification of basic geographical information data of different coordinate systems in Yichang City.