In order to explore the optimization of the mining effect of the gently inclined medium-thick orebody and the migration law of ore and waste rock, the gently inclined medium-thick orebody in the middle section of－400 m to－360 m in Caogou Mine was taken as the research background. Physical tests of three different mining sequences were designed to study the influence of mining sequence on the mining effect of orebody. The discrete element software PFC2D was used to study the migration law of ore and waste rock. The results are concluded as follows. Firstly, the ore recovery rate of the mining sequence III is 45.56%, the ore dilution rate is 19.29%, and the difference of recovery and dilution is 26.27%. Compared with the difference of recovery and dilution of the mining sequence I and the mining sequence II, the difference of recovery and dilution of stoping sequence III increased by 1.95 percentage points and 4.01 percentage points respectively. Therefore, the mining sequence III is the optimal mining scheme, that is, the upper caving orebodies of the No.3 and No.2 outlets being alternately mined for three cycles, then the upper caving orebody of the No.1 outlet will be continuously mined; and after the No.1 outlet being mined, the upper caving orebody of the No.2 and No.3 outlets will be alternately mined. Secondly, in the early stage of ore drawing, the displacement vector of ore and waste rock particles above and around the ore drawing port tends to the center of the ore drawing port axis. In the later stage of ore drawing, the displacement vector of ore and waste rock particles above the ore drawing port gradually tilts to the left. Thirdly, before the start of ore drawing and after the end of ore drawing, the contact force chain of ore and waste rock particles is in equilibrium. In the process of ore drawing, the contact force chain of ore and waste rock particles is in an unbalanced state.