Abstract: In order to study the gas migration law in goaf, the goaf in P41104 fully mechanized working face of Wangjiazhai Coal Mine was used as a model, and FLUENT software was used for modeling, a simulation study was carried out for three types of conditions, namely, different wind speed, temperature rise of residual coal and gas concentration overlimit in the upper corner.The results show that the ventilation condition has a great influence on the distribution of gas concentration field in the shallow part of the goaf, but with the increase of the strike and inclination distance, the influence of ventilation on the gas concentration field distribution in goaf will be very small; after the oxidation and temperature rise of residual coal in goaf, the gas concentration around the high temperature heat source increases with the increase of temperature, but the increase is small, and the high temperature heat source has less influence on the temperature field of the whole goaf; high level drilling gas drainage can effectively solve the problem of gas concentration overlimit in the upper corner.