Abstract: In the practice of controlling gas at the upper corner in working face by pneumatic fan, working effect of fan is affected by location, air outlet velocity and air outlet wind direction of fan. According to three influencing factors, three schemes of numerical simulations are put forward based on FLUENT in order to study on related technical parameters. By analyzing flow field characteristics of three schemes in upper corner, optimal parameters of three influencing factors are shown. The simulated results provide the basis for seleting technical parameters which control gas at upper corner by pneumatic fan in practice. Good effect is achieved in practice.