A filtering device (100) for highly viscous media comprises at least one screen plug (10) which is movably arranged in a screen plug bore (27) of a housing (20) and which has at least one screen cavity (11, 12), a filter element (11.7) lying in said screen cavity. The screen cavity (11, 12) narrows to a funnel section (11.6) in a rear region when viewed in the flow direction, said funnel section opening into at least one screen plug outlet channel that opens upstream of the housing outlet channel (24, 25) in the production position. According to the invention, the screen plug outlet channel comprises an inlet zone (11.1, 11.2), at least one deflecting point (11.3), and an outlet zone (11.2, 12.2). The intake zone (11.1, 12.1) extends from an edge region of the funnel section (11.6), and the outlet zone (11.2, 12.2) is designed as a groove that extends on the outer face of the screen plug (10, 10′) and/or on the inner face of the screen plug bore (27).