The invention relates to a device for filtering fluids, notably plastified, thermoplastic materials, containing impurities, particularly in the form of solids. Said device comprises a case (1) containing at least one fixed, substantially level filter (5). The fluid to be filtered is fed to the filter (5) in the area around its periphery by means of at least one inlet channel (3). The filtered fluid is led out of the case (1) via at least one outlet channel (7). At least one scraping element (17) is pressed with its scraping edge (31) against the inlet-facing surface (11) of the filter (5), and is movably fixed to a support (12) which can be rotated by a drive element (15) around an axis (14) substantially perpendicular to the inlet-facing surface (11) of the filter (5). The scraping element (17) scrapes off the impurities adhering to this surface (11) and moves them to the centre of the filter (5), from where they are evacuated by means of at least one endless screw (38) via at least one evacuation channel (39) starting at the centre of the filter (5) and leading out of the case (1). At least one scraping element (17) is fixed on a support (12) in such a way that it pivots around an axis (18) and sticks out from said axis in the direction of the rotation of the support (12) and at an oblique angle to the filter (5). The scraper edge (31) of the scraping element (17) is pressed against the filter (5) when the support (12) rotates as a result of the counter-pressure generated by the fluid to be filtered. This effectively prevents blockages of the scraping elements (17).