The stainless steel filter is composed of a shell, a multiple element filter, a backwashing mechanism, and a differential pressure controller. The inner chamber of the stainless steel filter is divided into upper and lower chambers by a diaphragm inside the shell. The upper chamber is equipped with multiple filter elements, which fully utilizes the filtering space and significantly reduces the volume of the filter. A backwashing suction cup is installed in the lower chamber. During operation, the turbid liquid enters the lower chamber of the filter through the inlet and then enters the inner chamber of the filter element through the baffle hole. Impurities larger than the gap of the filter element are intercepted, and the clean liquid passes through the gap to reach the upper chamber, and finally is sent out from the outlet.