The study explored how to improve gob side entry retaining by roof cutting in inclined coal seams with thick, inclined, and hard roofs. The research focused on optimizing key parameters through theoretical analysis, numerical simulation, and field monitoring at the 1301 headentry of Great Wall No.6 Mine. Firstly, based on the expansion coefficient of rock crushing and masonry beam theory, the theoretical minimum values for the roof-cutting height and angle of the 1301 headentry are derived. Secondly, the theoretical derivation results were further optimized by creating a model of gob side entry retaining using roof cutting in the 1301 working face with the help of PFC2D numerical software. The response characteristics of stress, displacement, and fabric tensor of the roof were compared and analyzed under different roof-cutting heights and angles to enhance the accuracy of the results. The analysis shows a logarithmic relationship between roof-cutting height and pressure relief, where the pressure relief effect decreases as roof-cutting height increases. There is an "S" relationship between the roof-cutting angle and the pressure relief effect; as roof-cutting height increases, the pressure relief effect initially increases and then decreases. The best roof-cutting height and angle for gob side entry retaining in the 1301 headentry of No.6 Great Wall Mine are 13m and 10°, respectively, according to theoretical analysis and numerical simulation. The field monitoring shows that the control effect of surrounding rock under the parameters of roof cutting is good. The deformation of the rock surrounding the retaining roadway is significantly reduced, which effectively meets the mining requirements of the next working face. This verifies the effectiveness of the optimized roof-cutting parameters and provides a theoretical basis and practical reference for selecting parameters for gob side entry retaining through roof cutting in similar conditions.