Abstract: The invention relates to a filter device for microfiltration of oil, in particular for use in engines, automatic transmissions and hydraulic applications. The filter device comprises a tubular microfilter cartridge through which medium can flow in the transverse direction and which has open ends. This filter cartridge is accommodated in a filter chamber which is enclosed by a filter housing and is accommodated between two end closure elements, between which the filter cartridge is clamped under prestress. On their surface facing towards the filter cartridge the end closure elements are provided with at least one rib which extends in the transverse circumferential direction of the filter cartridge. The holding means comprise a spring which acts with prestress on one of the end closure elements, in such a manner that his closure element follows the end wall which it adjoins in the event of longitudinal expansion and also in the event of longitudinal contraction.