Abstract: Energy conservation is one of the most important and economical ways to achieve the targetsof Carbon Emissions Peak and Carbon Neutrality in our country. Waste heat is largely discharged intothe environment during the engine operation resulting in the low engine working efficiency. The technol⁃ogy of semiconductor thermoelectric generation based on the Seebeck effect has great advantages inwaste heat utilization from engines, which has been attracting extensive and intensive researches. Thisstudy introduces the working principle of thermoelectric generation, the device structure, and the com⁃ponents of the thermoelectric generation system. A review of thermoelectric generation research at homeand abroad isalso presented, in which the R&D status, application potential, evaluation metrics, andcurrent challenges of thermoelectric materials and systems are analyzed. Several key scientific problemsthat affect the performance of the waste heat thermoelectric generation system, including thermoelectricefficiency and overall power generation efficiency, are proposed, and the corresponding preliminary so⁃lutions are given. The non-uniformity of the hot-end temperature distribution is one of the essentialproblems to design a high-performance waste heat thermoelectric generation system. In addition, theinherent contradictory between heat collection efficiency of the heat collector and pressure drop shouldbe balanced to achieve the maximum fuel saving rate. Besides, new issues and data in application dem⁃onstration project of engine waste heat utilization have been presented to provide a useful guidance forfuture studies.