The ocean, which covers about 70% of the earth surface, contains abundant natural resources, such as organisms, minerals, energy resources, and etc. Development and utilization of ocean resources is an important way to solve the problems of population, resources and environment that human beings are confronting with. Besides, the underwater operation equipment plays an important role in the development and utilization of the ocean. The rotary dynamic seal, which exerts great effects on the static and dynamic performances, reliability, life span and etc. is a key technology of the underwater rotating equipment. This research focuses on the frictional properties of rotary dynamic Glyd-ring under water lubrication. A physical model is proposed to study the effects of rotational speed and working pressure on the maximum Von Mises stress numerically. A rotary seal test bench is developed and experiments have been carried out to investigate the friction, torque of Glyd-ring under different rotational speed, different sealing pressures on one or both seal sides. The research results provide a basis for the design of dynamic seals for deep sea equipment.