Owing to the effects of human activities and climate change,the natural hydrological series lost their consistency. In order to adapt to a changing environment demanding for hydraulic engineering design, inconsistent annual runoff process design method based on extreme value with common frequency was proposed. Firstly,the hydrological variation diagnosis system(HVDS)was used to analyze the variation of different time scales runoff series and their annual distribution features. Secondly, according to the variation point,annual average flow series was divided into several time periods. Thirdly,the frequency distributions of different time scales runoff series before and after the change-point were conducted based on the hydrological frequency calculation theory for inconsistent series (HFCT) and the difference of means and various frequency characteristic values were analyzed. Finally,the method of extreme value with common frequency was used to calculate the annual runoff process in each time period. This study was applied at Lingxia station in Dongjiang River, and the inconsistent annual runoff process was designed. The difference of designed annual runoff process before and after the change-point at Lingxia station was analyzed. The results are valuable for the planning and design of hydraulic engineering in Dongjiang river basin.