Pepper is an important vegetable crop in China.The price fluctuation has a significant impact on the development of the pepper industry.To explain the fluctuation of pepper price,the monthly price of the national pepper in 2004—2018 is used as the research object,descriptive statistics,X12 seasonal adjustment model,the H-P filtering method are used to decompose the price fluctuation of pepper.The results showed that the pepper had obvious seasonality and periodicity,and the time span of each cycle was different,and the fluctuation range was different.The causes of pepper price fluctuations,grasp the changing rules of pepper prices were analyzed to provide feasible suggestions for the development of Chinese pepper industry.