The invention relates to a graphical application system for multiple DSP (Digital Signal Processor) chips and an application method thereof. The application system comprises an upper computer, a communication management board and a main control board; the upper computer is connected with the communication management board by the Ethernet; the communication management board is connected with an FPGA (Field Programmable Gate Array) chip of the main control board by a backplane bus; and the FPGA chip of the main control board is connected with at least two DSP chips. The application method comprises the steps of: carrying out writing, compiling and management of graphical application on a PC (Personal Computer); downloading a compiled executable code into the DSP chips of an application target by a network communication protocol; and after powering on embedded application systems of the DSP chips again, loading the executable code of the graphical application so as to complete the graphical application of multiple DSP chips. According to the technical scheme provided by the invention, the difficult problem of large-scale programming is solved, control and protection on a power system are well designed, and the requirements of a high-voltage high-capacity flexible DC (Direct Current) system for controlling and protecting system software are met.