A filter device is disclosed having a round filter element having a filter medium body with an open interior. The filter element is installable into a filter housing having a base filter housing and a housing cover, in which an inflow opening of the cover overlaps against and aligns with an inflow opening of a base housing part such they form a continuous inflow opening. A support mesh cage arranged on the radially outer wall of the annular filter medium body. The filter housing has a longitudinally extended cross-sectional shape in which the inflow opening and an outlet opening are both arranged on the base housing part at opposing sides of the base housing part.