Abstract: In order to determinate gas loss amount when coal cuttings desorbed,the gas desorption experiments for underground drilling cuttings in Dingji coal mine of Huainan mining area was done.Isobaric desorption experiment for coal cuttings samples was done in sampling locations by using sampling method of eliminating chips by wind power and accessing coal sample directly from the orifice.Taking nature initial desorption 20min of coal cuttings as the reference time period,then the relationship,q=0.035 t^-0.45,between coal cuttings initial velocity and desorption time in initial desorption was deduced,and the empirical formula of gas loss and exposure time was Q_s=0.064t₀^0.55.