Abstract: An air intake filter for internal combustion engines has a flat, replaceable filter insert through which air passes transversely in operation, and which can be inserted from one side into a filter housing. The filter insert has a gasket arranged on its periphery for sealing an end face of the filter insert against a lip on the filter housing. Sealing pressure is exerted by ledges on lateral portions of the filter housing which slant toward the filter insert in the direction of insertion. To prevent the gasket from being displaced laterally with respect to the lip on the filter housing when the sealing pressure is applied, the filter insert is received in a substantially open-faced frame.