The utility model provides a mechanical stirring type walnut shell filter and relates to an oily sewage processing device. A water distributor is arranged on the inner upper portion of a tank, and an integrated water collection device is arranged on the inner lower portion of the tank. A walnut shell filtration material layer is arranged on the integrated water collection device. A stirring device on the top of the tank and a stirring shaft end output from the stirring device are movably connected with the integrated water collection device. A toothed stirrer is arranged on the stirring shaft. An overflow exhaust port is formed in the top end of the tank. A non-filtered water inlet is formed in the side wall of the tank and communicated with the water distributor. A filtered water outlet is formed in the bottom of the tank. According to the mechanical stirring type walnut shell filter, the reasonable water distributor and the water collection device are adopted and simplified in structure, and troubles to corrosion prevention and other subsequent processes are avoided. The stirrer with the toothed end face is adopted, so that the probability of rubbing and collision of walnut shell filtration materials in backwashing is increased; a conventional air water soft washing mode is changed to a mechanical strong washing mode, and therefore the technical problems of filtration material hardening, biological agglomerating, oil adhering and others in backwashing are solved.