The invention relates to the sphere of medical devices, in particular to dental units and can be used in their suction systems. Filter for suction system of dental unit has a connecting module which has inlet and outlet hoses of content moved from suction system, single use filter consisting of the container receiving the content from suction system, rigidly attached covering in it and lock-fixer with a possibility of rotation installed in the covering. On the inner surface of module there is made a pipy projection concatenated with the output of module and a hole concatenated with the input of module, which are provided for attaching the filter to the module. Fixed notches are made on the side face of module. On the inner surface of covering are made inlet and with preventing mesh outlet holes and fixing projections on the outer surface of covering with a possibility of fixation in the fixing notches on side face of connecting module. The lock-fixer of covering has inlet and outlet pipy projections. The safety of filter system servicing is ensured, service time is reduced.