Abstract: In order to make up for the insufficiency of the complex shape working face deformation prediction,and to improve the adaptability and accuracy of the mining subsidence deformation prediction,subsidence prediction method of complex shape working face based on improved triangulation algorithm is built.In this method,an improved triangulation algorithm is introduced,and key methods such as coordinate system conversion and correction of inflexion migration are optimized,the subsidence prediction model of complex shape working face is established based on probability integral method.In this model,the working face is split into multiple triangles by using the improved triangulation algorithm;then,the variable step-size Simpson double integral method is adopted to conduct subsidence prediction in triangular units,and the impact of the entire working face mining on the surface mining subsidence can be obtained through summation method;finally,other movement and deformation prediction values can be received in turn according to probability integral method.Based on MATLAB software,the subsidence prediction program of the model established in this paper is developed.The simulation results show that the predicted insertion points of the model are all distributed on the expected subsidence curve of the conventional probability integral model,which indicated that the model could predict the mining subsidence deformation of irregular working face with complex shape.The test results of the 1414（1） working face of Guqiao Mine in Huainan City show that the fitting effects of the prediction subsidence curve and the measured subsidence curve is good,the absolute error of prediction subsidence curve is from 0.2 mm to 359.2 mm,the relative error is 25.02%,and the medium error is 101.9 mm,which can meet the requirement for engineering application.