To provide an oil recovery system in which manual work is reduced even at a high position or in a narrow place, and an oil recovery work can be made in a short time.

The oil recovery system is provided with a coupler 22 for discharge installed in an object to be oil-recovered, a coupler 23 for connection fitted by pressing against the coupler 22 for discharge, and a manual pump 24 to be connected to the coupler 23 for connection by a suction hose 25. On-off valves 39 and 45 to open and close the oil passage are built in both the couplers 22 and 23. The on-off valves 39 and 45 are connected by pressing the couplers 22 and 23 mutually to open the valves. The manual pump 24, which is provided with cylinders 27 and 31, makes the cylinder 27 inside negative pressure by reciprocating the piston 31, and sucks the oil by the action of the negative pressure.