The hydraulic fracturing mechanism of carbon shale is studied by finite element method. However, conventional methods have problems such as lack of quantitative analysis, research limitations, and expensive experimental costs. In this project, the stress distribution and crack propagation path of carbonaceous stone slab are studied by numerical simulation. By numerical simulation, it is found that the maximum difference of fracturing cracks is only 1.3 mm/s and the maximum value is about 10 mm/s. The research results of this project can deepen the understanding of the mechanism of carbonaceous plate fracturing and lay a foundation for the popularization and application of this kind of fracturing technology. The research results can lay a theoretical foundation for the optimization of hydraulic fracturing construction scheme and effect prediction of carbon slate.