A filter (430) of a surface cleaning apparatus. The filter (430) is detachably arranged inside a recovery storage part (400) to perform solid-liquid separation on recovered solid and recovered liquid, which are recovered by a cleaning base part (600); the recovery storage part (400) is divided by the filter (430) into a plurality of cavities, and the plurality of cavities at least comprise a cavity for storing the recovered solid, a cavity for storing the recovered liquid, and a cavity for carrying out gas-liquid separation; and the filter (430) comprises an anti-surge device, and the anti-surge device is at least arranged between the cavity of the recovery storage part (400) for carrying out gas-liquid separation and the cavity thereof for storing the recovered liquid, so as to prevent, in the process of posture changing of the surface cleaning apparatus, waves generated by the recovered liquid from interfering with gas-liquid separation carried out in the cavity for carrying out gas-liquid separation. Further provided are a recovery storage part (400) and a surface cleaning apparatus.