With the rapid social and economic development, China has become not only No.1 market in the world for the automotive industry since 2010, but also its used-car market has been developing fast in recent years. Through the environmental analysis (Political, Economical, Social and Tecnological factors) and big data collected from local institution and association , the reason behind this phenomenon is shown. with further findings by comparing Chinese local market with mature markets (Europe, America and Japan), Chinese used-car market has still huge space of growth. And the driving forces from other aspects (Electrilization, E-Commerce, etc) will become new incentives for the future.