Air cleaner

An air cleaner including a casing body (26) and a sealing frame (27) is disclosed. The casing body has a fitting part (39) for allowing engagement of the sealing frame therein. A filter (28) is mounted inside the sealing frame in a tightly contacted relation with the latter. The sealing frame has a groove (47) extending along its outer peripheral surface (44a) and opening on its front surface (42).