Abstract: In the liner cementing operation of oil drilling, the water hole of the hydraulic cylinder slip setting system in the traditional hydraulic liner hanger is normally open, which is prone to premature setting caused by false triggering of circulating pressure, and seriously threatens construction safety. To solve this core problem, an electronic control mechanism for pressure transmission of the downhole hanger hydraulic cylinder is developed. Based on the principle of pressure wave signal triggering, this mechanism realizes the controllable opening of the hydraulic cylinder: the pressure wave preset at the wellhead is detected by the downhole pressure sensor and analyzed by the single-chip microcomputer, which then drives the motor to open the water hole valve. In terms of structural design, an annulus nipple is adopted to form an absolute pressure space for housing the electronic control system. The core components are domestic high-temperature-resistant and low-power-consumption elements, and the valve body is made of 2A12 aluminum alloy with complete strength verification. Meanwhile, by establishing the material constitutive model of the O-ring seal and combining finite element simulation, the sealing performance under different medium pressures and rubber hardness is systematically studied to verify the reliability of the valve core sealing; friction analysis of the sealing structure and matching verification of motor thrust are also carried out. The strength verification results show that the safety factor of the valve body reaches 1.16 under the ultimate pressure of 50 MPa, meeting the design requirements; the sealing performance analysis confirms that the valve core sealing maintains reliable performance under various working conditions; the ground pressure-bearing test indicates that the mechanism has stable pressure-bearing performance and can effectively solve the premature setting problem. This device is adaptable to the complex working conditions of deep wells, provides a strong guarantee for the safe and efficient implementation of liner cementing operations, and has significant application value.