Carbon prices are low and fluctuate greatly since Chinese carbon emissions trading scheme pilots were operated. This paper discusses the price drivers in the pilots, using structural breaks test and autoregressive distributed lag model. The results indicate that oversupply of allowances, low auction prices and use of China certified emission reductions will cause remarkable decline on carbon prices; the expansion of carbon market and centralized trading will rise carbon prices. Oil prices are positively correlated with carbon prices, and coal prices are negatively related with carbon prices. Carbon-intensive product prices also affect carbon prices. Chemical prices are positively linked with carbon prices in Shenzhen, while negatively related with those in Beijing and Shanghai, for differences in sectoral coverage. Nonferrous prices have positive impacts on carbon prices in Beijing but negative impacts on those in Shenzhen, for differences in industrial structure. Financial markets and weather have limited impacts on carbon prices. Our results provide policy implications for the development of pilots and the national carbon market.