The utility model discloses a heat pump for recovering waste heat of oil extraction discharged sewage, and belongs to the technical field of oil extraction equipment. The heat pump comprises a generator, a condenser, an evaporator, an absorber and a heat exchanger. Wherein the generator comprises a hearth for combusting gas and a container for loading a lithium bromide aqueous solution, the top ofthe container is connected with the condenser through a first water vapor pipeline, and the bottom of the container is connected with the absorber through a first lithium bromide solution pipeline; the bottom of the condenser is connected with a liquefaction pipeline, the liquefaction pipeline is connected into the evaporator, and a heating medium water pipe penetrates through the condenser; thetop of the evaporator is connected with the absorber through a second steam pipeline; a waste heat water pipe penetrates through the evaporator; the bottom of the absorber is connected with the generator through a second lithium bromide solution pipeline, and a heating medium water pipe penetrates through the absorber; the two lithium bromide solution pipelines are intersected at the heat exchanger; according to the heat pump, under the condition that an original production process is not changed, waste heat utilization can be achieved, and the purposes of saving energy, reducing emission andreducing operation cost are achieved.