Abstract: In the process of unconventional oil and gas resources development, the formation of complex fracture networks through hydraulic fracturing is one of the key technologies to achieve efficient development.The change of reservoir pressure field during fracturing has an important influence on fracture propagation.Based on the extended finite element theory, a dynamic fracture prediction model based on coupled damage-filtration-stress is established in this paper.The influence of reservoir pressure distribution on fracture dynamic propagation, fracture initiation pressure and extension pressure is studied for simultaneous fracturing and sequential fracturing.The degree of hydraulic fracture deflection and pressure changes are analyzed under different reservoir pressure increment conditions.The research results show that the increase of local reservoir pressure induced by fracturing fluid leak-off will changes the reservoir pressure field, which increase the deflection of hydraulic fractures during the extension process.At the same time, the extension pressure and initiation pressure of hydraulic fractures will increase.The calculated case shows that the initiation pressure and extension pressure of the crack will increase by 27.49% and 27.58%, respectively.Comparing the fracture propagation performance of synchronous fracturing and sequential fracturing, it is found that the deflection of the fracture is larger and the extension pressure of the crack is higher for sequential fracturing.The research results can provide theoretical basis and technical support for the effective development of tight sandstone reservoirs.