Maintenance system and method of embedded system

The invention discloses a maintenance system and method of an embedded system. The maintenance system comprises a mobile storage device with stored fresh program and a maintenance mode starting unit and a software brushing and writing unit which are stored in an embedded system guide program; the maintenance mode starting unit is used for recognizing the mobile storage device and starting the maintenance mode of the embedded system after the recognition; the software brushing and writing unit is used for brushing and writing the fresh program into the embedded system after the maintenance mode is started. According to the maintenance system, the existing mobile storage device recognizing function and software brushing and writing function of a guide program are utilized, the functions of the maintenance mode starting unit and software brushing and writing unit of the maintenance system can be realized, additional maintenance programs arranged in the embedded system are omitted, precious storage space of the embedded system is saved, the system design complexity is low, maintenance safety is improved, and the on-site maintenance of the embedded system can be benefited by the maintenance operation.