Different gas drainage effect provides reference for gas prevention and control. Based on continuous equations of gas flow, momentum equation and energy equation, gas drainage model was set up to simulate pipe buried drainage, pipe buried and high drilling drainage, pipe buried and high drainage with upper corner drainage , the result showed that the third drainage technology had the best drainage effect with gas content below 1%, gas drainage above 60%, gas out of limit got control in air return roadway, met the needs of safe mining.