Abstract：In view of the problem that the gas accumulation at upper corner in fully mechanized coal face with sublevel caving seriously affects coal mine safety production, the distribution of gas volume fraction field at the upper corner in the coal face 12318 of Wangjialing coal mine the relationship between the distribution law of gas volume fraction field in the coal face and the gas pumping at the upper corner. The results showed that gas concentration at the upper corner in the side near the gob and outside of the air-return in the coal face 12318 was higher than that in other area, where the maximum gas concentration was 0. 5%; while gas volume fraction at the upper corner in the side near the coal face was lower, where gas concentration only was 0. 1% ～ 0. 25%.According to the conclusions, the comprehensive gas control methods such as gas drainage by high-position oriented and horizontal long holes and pre-embedded or inserting pipes were put forward, and when gas volume fraction at upper corner effectively was reduced from 0. 7% to around 0. 3%.