Abstract: When sealing liquid with magnetic fluid, the relative movement between the magnetic fluid and the sealed liquid caused by the shaft rotation leads to the stability problem of the interface, and the sealing performance is poor. The spiral seal can prevent the leakage of the sealed liquid by using the fluid dynamic pressure when the shaft rotates. To reduce the influence of the shaft speed on the sealing performance, a combined magnetic fluid and spiral seal for sealing liquid is designed, and the combined seal experiment platform is set up. Theoretical and experimental results show that the combined seal structure can not only solve the problem of failure of the magnetic fluid seal at high speed but also solve the spiral seal leakage problem during parking and low speed, achieving more stable sealing performance at different speeds.