The current status of ORC waste heat power generation technology  at home and abroad is introduced. The ORC waste heat power generation system is a Rankine cycle with low-boiling organic matter as the working fluid. It is a waste heat power generation technology that can efficiently convert low-grade thermal energy into electrical energy. It is mainly composed of three parts: the flue gas waste heat recovery system, oil-organic working fluid heat exchange system and organic working fluid power generation system. Its working principle is the same as that of the SRC waste heat power generation system. By comparing the composition and power generation efficiency of ORC and SRC waste heat power generation systems under different conditions, the selection principles of ORC and SRC waste heat power generation systems are proposed.