Abstract: For implementing every forestland border and utilization to the land,the definition of forestland border was the foundation of implementing national provincial and county levels forestland planning,protection and utilization and it was also the basement of national forestland map establishment.This study focused on the needs of Sichuan province definition of forestland border,analyzed the workflow,built the methods of layers standardization,forestland polygons attributes complement,forestland polygons quick-merge and auto-merge,designed the structure and functions of Sichuan definition of forestland border software.The software has already been widely applied to the practical work of definition of forestland border in more than 100 counties of Sichuan Province,experience had proved that the application of the software not only effectively ensured the consistency of forestland polygons data,but also reduced the difficulty and complexity of definition of forestland border,it was easily realized and have very good practical value.