Abstract: A scheme of ventilation control in mine based on H_∞ optimization control technique was (presented.) A dynamic model with main air flow as current state and ouput power of main fan as control input for the system was built. And in the model, the environment interference and the detection lagging for gas in practices were taken in account. For the model, an H_∞ control strategy with output feedback from gas observers and consideration of control cost were given. The simulation result showed that it is one of the best strategies in the same field under the requirement of the optimization in both technology and economy.