Abstract: The invention relates to an improved cleansable filter intended for filtering natural water for the irrigation of cultivated fields. The filter comprises a cylindrical body, a filtering element mounted inside said body and defining in the interior two concentric chambers, one communicating with the exterior through a drainage valve, and also through one of two lateral openings in the body. The other annular chamber encloses the first chamber and communicates with the exterior through the other lateral opening. The filter also comprises a brush mounted coaxially in said first chamber, said brush being rotatable manually or automatically from the exterior of the filter, and removing all foreign bodies from the inner wall of said first chamber. The liquid to be filtered enters the annular chamber through a lateral opening, passes into the first cylindrical chamber and through the filtering elements from the interior to the exterior, and leaves by the second lateral opening.