The invention discloses an environment-friendly drainage drain of a kitchen sink. The drain comprises an outer drain sleeve and an inner drain sleeve, wherein the inner drain sleeve is rotatably inserted with the outer drain sleeve by virtue of a screw thread; a filter screen is paved on the top end face of an inner ring of the inner drain sleeve; a fixed seat is embedded in the central end face of the filter net; an operating rod is rotatably inserted in the central end face of the fixed seat; a gear disc sleeves the top of the operating rod by virtue of a connecting rod fixing sleeve; a gearis fixedly arranged at the top end of the part where a sealing plate and a rectangular drain hole are hinged; the gear and the gear disc are located on a same horizontal plane and are mutually meshed; the bottom of the operating rod rotatably runs through the bottom end face of an inner cavity of the inner drain sleeve and extends to the part under a second hemispherical water outlet; and a firstvacuum airbag and a second vacuum airbag sleeve the operating rod in a sliding mode. The environment-friendly drainage drain of the kitchen sink provided by the invention, in daily use, can isolate foreign smell and prevent overflow, and the drain can also accelerate a drainage flow rate, so as to facilitate detaching and cleaning.