In order to obtain the optimal support scheme of roadway under the influence of repeated mining, Shaanxi Binchang Xiaozhuang Mine was taken as the research background, and the plastic failure characteristics of roadway under different support schemes were simulated by 3DEC discrete element numerical simulation experiment method. The optimal spacing of bolts under different support schemes was obtained, and the optimal support scheme was given. The results showed that under the disturbance of repeated mining, the failure mode of roadway was mainly shear failure, and the failure range of the left goaf side of roadway was smaller than that of the other side. This result was caused by pressure relief after mining of the upper working face. As the row spacing between bolts decreased from 900 × 900 mm to 800 × 800 mm, the development degree of rock cracks around rectangular roadway decreased, the expansion range of cracks decreased, and the deformation of surrounding rock of roadway decreased continuously. Considering the support effect and support cost of the roadway, the row spacing between the bolts was 850 × 850 mm, and the combined support form of the roadway was given when the mining influence was large.