Abstract: In order to more quickly and conveniently estimate the coal loss caused by the spontaneous combustion in the coalfield,taking the coal spontaneous combustion area in Wuda Coalfield as the study object, the paper discussed the relationship between the ground sub-sidence and the coal type in the coal spontaneous combustion area of the coalfield and provided a method of InSAR applied to monitor the deformation within the regional scope.The ground subsidence data were obtained with the phase information of the SAR data.The DEM images of the coal fire deformation region were established.In consideration of the ground subsidence coefficient occurred from the different coal type and the different components of the coal type, the theoretical formula of the coal effective loss was derived and calculated.Ac-cording to the type of the coal spontaneous combustion and the equivalent mining theory,the theory to approve the feasibility of the method was provided.The results showed that when the coal effective loss was estimated,the consideration of the coal type was necessary.