The utility model discloses a pump with double-layer sleeve type inlet and outlet channels. The pump comprises an outer pipe (1), an inner pipe (4) and an impeller (3), wherein the inner pipe (4) is arranged inside the outer pipe (1), and the impeller (3) is connected with a pump shaft and arranged inside the inner pipe (4). An annular cavity between the outer pipe (1) and an inner pipe (2) forms the first pump inlet and outlet channel, and the inner pipe (2) forms the second pump inlet and outlet channel communicated with the first pump inlet and outlet channel. Due to the adoption of the structure, the pump is simple and compact in overall structure and convenient to obtain. Pump inlet and outlet pipelines are omitted, and therefore a fluid system is arranged compactly, and meanwhile the potential hazard that the long pipelines are damaged is eliminated.