Abstract: Taking the goaf spontaneous combustion situations in close distance coal seams mining of a northwest mine as the background, through theoretical analysis, field test and numerical simulation, we study goaf spontaneous combustion of adjacent coal seam. The research results show that in the close distance coal seams mining, with the increasing alternate distance of the upper and lower seams, goaf oxygen concentration and lower coal spontaneous combustion with maximum width decreased; the maximum wind speed and the spontaneous combustion with minimum width did not change obviously with the increase of separation, only a small rise; the upper limit of upper layering in the gob, the lower oxygen concentration and spontaneous combustion zone width are increased. The maximum distance of lower limit oxygen concentration and maximum distance spontaneous combustion with the maximum width and the maximum wind speed change trend. Depth became smaller, the oxygen concentration from the working face goaf in working face is close position, and oxygen concentration distribution line is relatively dense, after about 25 m away from working face, oxygen concentration changes gradually slowly, and depth in the mined-out area presents the "Γ" distribution.