The HY-2A satellite ground application system is one of five HY-2A satellite project systems, which has the function of satellite data receiving, processing, calibration and validation, and data application etc. HY-2A satellite ground application system has steady receving system at Beijing, Sanya and Mudanjiang station, which can receving real time data in the waters around China. In addition, it has some subsystem, such as data preprocessing, processing, precise orbit determination, data archiving and distribution, data application etc in the Beijing data precessing center, which can processe all level data of the HY-2A satellite and distribute to user every day. In this paper, it is shown an overview of HY-2A satellite ground application system and an introduction to some main subsystem of HY-2A satellite ground application system, such as subsystem structure, function and operational flow etc.