To provide a pump gate which can greatly reduce the quantity of residual water below the lowest absorbed-water level of a drainage pump by dramatically lowering the lowest absorbed-water level.

A cut-off gate door body 3, which is ascendably/descendably provided in a boundary part between one water way 1 and the other water way 2, is constituted so as to ascend/descend (open/close) by an opening/closing means 6; and the drainage pump 4, which is composed of a horizontal-shaft underwater pump, is installed in the door body 3. The drainage pump 4 is installed in the door body 3 in such a manner as to have a tilted axis C1 tilted with a downward pitch toward the side of a suction port 5; and the suction port 5 is formed in a horizontally expanded flat shape wherein a horizontal width W is set adequately greater than a vertical height H.