Abstract The research of cement sheath stress in horizontal well fracturing plays an important role in horizontal well fracturing analysis, and is also related to the work of horizontal wells to a certain extent. The core work of the shaft is also affected by its cement sheath, so we should pay attention to the actual control of the cement sheath pressure in the actual work process to ensure that the cement sheath analysis is more effective. In this paper, the stress distribution model of casing-cement sheath-formation system is established. Through the model analysis, the whole stress analysis is completed, which is of great significance to the subsequent wellbore integrity control.