Abstract: An air intake filter for internal combustion engines has a flat, replaceable filter insert 20, through which the air flows transversely in operation, and which has a gasket 22 disposed on the periphery for sealing at the face side against a ledge 15 of the filter housing 11. The insert can be inserted into the filter housing through a narrow side, the sealing pressure being produced by a cover 50 which has two sliding wedges 51 and 53. To bring it about that, when the sealing pressure is applied, the gasket 22 will not be shifted laterally with respect to the ledge 15 of the filter housing 11, the cover, which is in the form of a substantially open frame, replaceably accommodates the filter insert. The cover is provided with cams 40 and 41 which serve to fix the frame 30 in an extended position during the replacement of the filter insert.