The invention discloses a waste heat integrated-utilization system for a natural gas heat-transfer oil furnace. The waste heat integrated-utilization system comprises a furnace body, a heat exchange coil, a nozzle and a flue gas pipe; the furnace body is internally provided with a hearth used for heating heat-transfer oil; the heat exchange coil is disposed inside the hearth; the heat-transfer oil flowing by the heat exchange coil is heated in the hearth; the nozzle is disposed on the upper end wall of the furnace body and is used for injecting natural gas and combustion-supporting air into the hearth for combustion and heat release; the flue gas pipe is connected to a flue gas outlet of the furnace body and is used for discharging the flue gas to a chimney. A first heat exchanger and a second heat exchanger are arranged in order inside the flue gas pipe, air from an air source flows by the first heat exchanger and is preheated before being delivered to the nozzle, and the natural gas from a natural gas source flows by the second heat exchanger and is preheated before being delivered to the nozzle. In addition, the system further comprises a waste heat generating set composed of a Freon evaporator, a double-screw generator and a Freon circulation loop; the waste heat generating set is used for further recycling waste heat of the flue gas flowing from the second heat exchanger.