Abstract: The in-situ stress field is an important factor affecting the stability of surrounding rock, and accurately inverting the stress field is difficult in mining engineering.Based on the Kaiser method for measuring in-situ stress data at the Buertai Mine, a calculation method for the stress field based on an improved combined spring model is proposed, and the results are compared with the results and measured values of the lateral pressure coefficient method and the classical combined spring model method.Using FLAC^3D, the stress dis-tribution law of the 42105 working face in the Buertai mine under different lateral stress boundary conditions was studied, and compared with the measured stress data.The research results show that: the root mean square average error of the main stresses between the calculated stress field and the measured values using this method is 1.831, which is reduced by 14.6% to 42.2% when compared to other inversion calculation methods; the average symmetric absolute percentage error is 19.45%, which is reduced by 3.4% to 36.9% when compared to other inversion calculation methods.When the stress calculated by this method is used as the stress boundary, the average root mean square error between the simulated support force and the measured data is 66.55, which is reduced by 7.75% when compared to the lateral pressure coefficient method and 32.45% when compared to the classical combined spring model method.The average symmetric absolute percentage error is 15.75%, which is reduced by 6.61% when compared to the lateral pressure coefficient method and 20.67% when compared to the classical combined spring model method.Therefore, this method can accurately calculate the stress field and provide a reference for the precise simulation of the mining pressure law by providing new methods of applying stress boundaries.