A hermetic seal device (1) is provided with an annular seal section (5) formed of an elastic material. The inner peripheral surface of the seal section (5) has formed thereon: a main lip (10) which is in sliding contact with the outer peripheral surface (S1) of a rotating shaft (S); and a vacuum space-side sloped surface (11) which has a diameter gradually increasing from the maim lip (10) toward a vacuum space (V). A plurality of annular ridges (20) are formed arranged in the axial direction on the vacuum space-side sloped surface (11), the annular ridges (20) being in sliding contact with the outer peripheral surface (S1) of the rotating shaft (S) while the main lip (10) is in sliding contact with the outer peripheral surface (S1) of the rotating shaft (S).
