OBJECTIVES: The roles of regulation and competition in the pharmaceutical market have always been controversial issues in the academia and within policy establishment. In the past 20 years, China placed directly strict government control on pharmaceutical pricing. A new policy which required deregulation on drug prices was introduced in China in 2015. The purpose of this study was to examine the time-series features of drug prices before and after the reform and to provide reliable evidence on the effects of China's pharmaceutical price regulations. METHODS: A retrospective longitudinal analysis was conducted using the 2011-2017 monthly pharmaceutical price data from Chinese national database. The analysis utilized the autoregressive conditionally heteroskedastic (ARCH) family of statistical models to characterizing the changes of drug prices. RESULTS: The drug prices presented an increasing trend with certain volatility during the observation period, especially after the pharmaceutical pricing reform in 2015. The reform exerted short-run effects on pharmaceutical price indexes, increasing them by 0.3 percentage points. Application of T-ARCH model provided evidences of no clustered features on the time-varying volatility. CONCLUSIONS: The drug prices increased in the short term after the reform of pharmaceutical pricing in China. Nevertheless, the price fluctuations have always been stable during 2011-2017. The China’s pharmaceutical market competition is being improved and the price deregulation reform in China would not bring about abnormal fluctuation on drug prices.