The invention relates to a fuel filter system, especially for Diesel engines, comprising a filter housing (1) having a fuel inlet (27) and a fuel outlet (29) and a dehydrating filter medium (23) between the inlet and the outlet for the fuel to pass through, the filter housing (1) having a collection chamber (35) for the water trapped by the filter medium from which collection chamber the water can be supplied to a water absorbing and evaporating device (49) via a controlled dispenser (45), the components of the evaporating steam being releasable into the environment through the evaporating steam outlet (51) thereof. The fuel filter system is characterized in that the water absorbing and evaporating device (49) comprises a valve arrangement (59, 61) by means of which the evaporating water outlet (51) can be closed depending on an inadmissible amount of non-evaporated water (55) collected in the evaporating device (49).