Moving away from a fixed exchange rate in 2005, China has gradually enlarged the band of fluctuations of Renminbi (RMB) and implemented various reforms on its central parity to have a more flexible exchange rate regime. This paper studies the nature of the exchange rate regime in China since the exchange regime reform of August 2015. Relying on the selfexciting threshold autoregressive (SETAR) model, it identifies endogenously the band of inaction beyond which the People's bank of China (China's central bank) starts to intervene in the foreign exchange market to restrict further fluctuations. Based on the comparison of the estimated threshold with the official band, this paper shows that the RMB/USD exchange rate followed an intermediate regime similar to the crawling band but with only one single threshold of intervention which is much lower than the upper boundary of the announced band.