In view of problems of single function and bad reliability of existing electrical parameters measuring system of gas power station of coal mine, the paper proposed a design scheme of electrical parameters measuring system based on DSP. The system takes DSP TMS320LF2407A as control core and can measure parameters of voltage, current, active power, reactive power and power factor of three-phase AC. The results of test and actual application showed that measuring error of the system is less than 0.5% and the system has higher reliability and better anti-interference ability.