Abstract: To address the challenges of conventional electro-hydraulic proportional valves failing in deep-sea hydraulic equipment due to the high-pressure and highly corrosive environment, structural improvements were designed for the proportional valve, enabling the development of deep-sea cable laying equipment. The approach involved the following steps. Firstly, the multi-way valve was sealed within a hydraulic oil-filled pressure chamber, utilizing a compensator to balance internal and external pressure. Concurrently, a novel electro-proportional multi-way valve （hereinafter referred to as the multi-way valve） was developed. Based on a conventional proportional valve, this design incorporates wet-type solenoids to achieve a pressure-resistant design for the solenoids. Subsequently, pressure-equalizing oil ports were machined within the valve body and around the solenoids to balance the pressure inside and outside both the valve body and the solenoids. This enables reliable operation of the multi-way valve under high hydraulic pressure conditions. Finally, the working performance of the multi-way valve under simulated deep-sea high pressure was investigated by pressurizing the sealed chamber. Test results demonstrate that under an oil pressure of 10 MPa, the output flow of each section of this multi-way valve remains stable, with flow hysteresis consistently around 10%. A good linear relationship is maintained between the current signal and the flow rate of each section, meeting the control accuracy requirements of the hydraulic system for the multi-way valve.