Abstract: Application at home and abroad shows that horizontal wells in low permeability reservoirs are often difficult to produce commercial value output if there is no fracturing and acidizing treatment. Subsection fracturing is the bottleneck of improving application effect of horizontal wells in low permeability reservoirs. Optimization of the multi-section fracture will determine the selection of fracturing technology and tools, and the ultimate fracturing effect. With the production rate after fracturing as objective function and numerical simulation as technical means, this paper studies 8 factors affecting the production of horizontal wells after subsection fracturing. This gives a reference basis to the optimization study of multi-section fractures in subsection fracturing of horizontal wells.