Given the incomplete field observation data of spontaneous combustion “three zones” in the gob area of the 6-2-103 fully mechanized top coal caving face at Huangzhuang Coal Mine in Huating, this study establishes a 3D model using Fluent software. Based on the coal seam characteristics of the mine, the spontaneous combustion “three zones” in the gob area of steeply inclined coal seams with high spontaneous combustion tendencies were analyzed, and field observation results were corrected. The study suggests that the height difference between intake and return air entries in steeply inclined coal seams necessitates consideration of temperature variations between the spontaneous oxidation zone and the working face, along with the unique structural geometry of roof strata in the gob area. The model incorporates on-site temperature observations, accounts for temperature differences between the oxidation zone and working face, and evaluates natural ventilation pressure’s impact on thermal distribution in the “spontaneous combustion zone”. Results show that air permeability decreases with depth in working face entries, being higher on the return side than the intake side. High-temperature spontaneous combustion and coal oxidation zones predominantly occur in the mid-upper section of the return side. Longitudinal temperature variation along the entry exhibits an initial rise followed by a decline. This research provides valuable references for fire prevention in steeply inclined working face entries.