Abstract: According to the status ofI type spontaneous combustion seam easy to cause a coal spontaneous combustion, taking No.10 seam of No. 1023 coal mini ng face in Yuandian No.1 Mine as a study object, a study was conducted on the spontaneous combustion oxidization law of coal in the goaf of No.1023 coal mining fac e.With the gas drainage pipeline in the goaf, the goaf temperature was measured and the dynamic variation of 02, CO2 density and others in the goaf with the coal mini ng face advanced were measured and analyzed.The results showed that the CO2 concentration distribution within the goaf could meet the air leakage filed distribution I aw of the goaf in the coal mining face with one source and one integration, and the air returning side would become a suffocation zone earlier than the air income side. The distribution scope of the spontaneous combustion three zones in the goaf would be that the no combustion zone was in a distance of 0 ~ 18.8 m to the central part of coal mining face, the spontaneous combustion zone was in a distance of 18.8~ 71.1 m to the central part of coal mining face and the suffocation zone was in a dista nce over 71.1 m to the central part of coal mining face.In accordance with the scope of the divided spontaneous combustion three zones, the lowest suitable mining spe ed of coal mining face calculated was 42 m/month.