PURPOSE: To provide a sealing device performing excellent liquid sealing in a wide range of pressure by preventing locking between sealing surfaces in a stop and a start of the rotation of the shaft, and by preventing leakage of the liquid in a full speed rotation.

CONSTITUTION: Relatively deep first grooves 22 and relatively shallow second grooves 24 are provided on one sealing surface 21 of two opposed sealing surfaces 19, 21 of a pair of seal rings 18, 20. The first grooves 22 are spiral grooves, and are optimized for hydrodynamic operation, and secure clearance by supplying the liquid to be sealed between the sealing surfaces 19, 21 during the rotation of a shaft 12. The second grooves 24 are designed to hydrostatically prevent a friction lock of the sealing surfaces 19, 21 at a start and a stop of the rotation of the shaft 12, and supply controlled amount of the fluid to be sealed between the sealing surfaces 19, 21 in a state of a stop or near the stop of the shaft 12.