With the continuous development of high power diesel engines toward the trend of high turbocharging, high power density, wide speed range and low emission, the matching problems between turbocharging system and diesel engine became more obvious, especially at low load and low speed. Sequential turbocharging system could match well with diesel engine in a wide operating range, which was thought to be the most mature technical measures to improve the performance of high turbocharged diesel engine. Therefore, the working principle of the sequential turbocharging system, the application, the research status and development trend at home and abroad were mainly introduced.