Abstract: To investigate the compressive deformation characteristics of broken rock in non-pillar mining with gob-side entry retaining by roof cutting and pressure relief, broken rock samples with different continuous gradations were prepared based on the Talbol grading theory. Compression tests were conducted using a self-developed compression device for broken rock. The effects of the Talbol power exponent on void rate, bulking factor, tangent modulus, and secant modulus were analyzed through the macroscopic compressive deformation behavior of the samples. According to the shape characteristics and failure phenomena of the broken rock, a compression test model was established using the PFC^2D discrete element particle flow software. Irregularly shaped broken rock particles were constructed with the FISH language, and the mesoscopic parameters were calibrated via numerical tests. Compression simulations were performed on broken rock particles with different particle size gradations, and the stress-strain relationship of the broken rock under confined conditions was verified by comparison with the experimental results. The variation laws of stress transfer, crack development, and lateral pressure with particle size gradation during the compression of broken rock were analyzed. The results show that the void rate, bulking factor, tangent modulus, and secant modulus of the broken rock are negatively correlated with the Talbol exponent. The stress-strain relationships obtained from the experiments and simulations are in good agreement, indicating that the compressive deformation process of broken rock can be divided into three stages: rapid compaction, slow compaction, and stable compaction. The development of micro-cracks during compression can also be divided into three stages: slow development, rapid development, and stable development. The higher the content of coarse particles, the more cracks occur in the final stable development stage. At a constant axial pressure, the lateral pressure decreases with the increase of single particle size, while there is little difference between different continuous gradations. Judging the blockiness of caved broken rock can provide a reference for the support of the gob-side rib in roof-cutting pressure relief and non-pillar mining roadways.