The utility model relates to a sealed oily recovery system of sealed gas chamber of thin oil belongs to the sealed gas chamber technical field of thin oil. Technical scheme is: the one end and the gas chamber bottom oil groove of drain pipe communicate, the other end and the wastewater disposal basin intercommunication of drain pipe, be equipped with drainage main valve A on the drain pipe in proper order, drainage main valve B and manual drain valve, the drainage main valve B on the drain pipe is passed through to the one end of automatic drainage pipe, the oil groove intercommunication of drainage main valve A and gas chamber bottom, U type structure has been constituted, the other end and the wastewater disposal basin intercommunication of automatic drainage pipe, be equipped with the profit separating device in the wastewater disposal basin, take the waffle slab to pass through the support to fix the bottom of separating the pipe at the profit in the profit separating device. The beneficial effects of the utility model are that: realize the automatic drainage of gas chamber, retrieved the sealed oil that runs off in the waste water well simultaneously, avoided the waste of the energy.