To provide a shaft seal device of a simple structure that can exhibit appreciable sealing performance and is small in power loss and abrasion.

The shaft seal device is provided with a seal ring 3 rotatable together which a rotary shaft 1, and a pair of non-rotatable static seal elements 4 and 5 in sliding contact with axial end faces 31 and 32 of the seal ring 3. The outer surface of the seal ring 3 and the outer portions of the paired static seal elements 4 and 5 define an intermediate chamber C therebetween. The seal ring 3 has a pumping hole 33 connecting the intermediate chamber C to an unsealed space B. The pumping hole 33 has a valve member 6 adapted to open during rotation of the seal ring 3 and to close during stoppage thereof. While the rotary shaft 1 and seal ring 3 rotate, the centrifugal pumping action of the pumping hole 33 increases pressure PC in the intermediate chamber C to counter leakage pressure from a sealed space A. When the rotary shaft 1 stops, on the other hand, the valve member 6 prevents sealed fluid from leaking to the unsealed space B via the pumping hole 33 that no longer provides the pumping action.