To provide a rotating shaft seal having high sealing performance and keeping its sealing function for a long period.

This rotating shaft seal comprises a first seal member composed of a rubber elastic body having a seal lip part kept into contact with an outer peripheral face of a rotating shaft, and mounted at a high-pressure side, a second seal member kept into contact with the outer peripheral face of the rotating shaft at its seal lip part formed by curving an inner peripheral edge to the high-pressure side, and mounted at a low pressure side with respect to the first seal member in adjacent to the first seal member, and a plurality of peripheral grooves formed on a part kept into contact with the seal lip part of the second seal member, of the outer peripheral face of the rotating shaft.