Abstract: This paper analyzes mechanical properties of subsea wellhead connector based on sealing property. Based on the criterion of sealing performance and Hertz contact theory, the paper discussed the quantitative relationship between contact width, maximum contact pressure and contact angle, and determines the reasonable range of inclination angle of sealing. Based on the elastic theory under the assumption of small deformations, the stress component function at each point of sealing ring is analyzed. Finite element software was used to analyze the stress variation of each point of the seal ring, and test was designed to verify the sealing performance.