The invention concerns a device for tangential filtering of a fluid to be treated, comprising in a housing (2): a separating part (15) mounted in the first communicating chamber (11), in sealed contact with the neighboring positioning plate (4), to divide said chamber into first (V1) and second (V2) volumes externally and internally delimited by the separating part and communicating with said two-way circuit, comprising a communication passage (24) between the first volume (V1) and the second volume (V2), internally equipped with a turbine (23) of a circulating pump, provided with a driving shaft (25) extending outside the first chamber (11) to be connected to a driving motor (26), and a closure housing (13) mounted sealed on a neighboring positioning plate (4), delimiting the first communicating chamber (11) and sealingly traversed by the turbine (23) driving shaft (25).