This invention provides an oil seal that can maintain an excellent friction reduction function over a long period of time, has excellent abrasion resistance, and further has excellent sealing properties. The oil seal comprises a seal lip (4) formed of a rubber-like elastic material comprising a lip edge part (9) and an air-side slope (8) and a sealing fluid-side slope (10) provided on both sides of the lip edge part (9). The air-side slope (8) has a coating film (14) on its surface. In the lip edge part (9) in its portion in contact with a shaft (13), a sealing fluid-side rubber part (2′) and an air-side coating film (14) are simultaneously brought into contact with the shaft (13). The coating film (14) is preferably formed of a coating agent comprising a fluororesin, a polyethylene resin, an isocyanate-modified polybutadiene resin, and a solvent.