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Based on the daily precipitation datasets of 158 stations in Sichuan from 1961 to 2014,the definition and characteristics of persistent heavy rainfall in the last 54 years in Sichuan, for the single station persistent heavy rainfall and the regional persistent heavy rainfall,are discussed,respectively. According to the first definition, the results show that the single station persistent heavy rainfall occurred in September frequently, and mostly in northwest，southwest, and northeast of Sichuan in the last 54 years. The single station persistent heavy rainfall usually lasts 3 days, and can bring 150 to 200 mm of rainfall to the local place. The frequency of the single station persistent heavy rainfall was 1 to 3 in the Panxi area. The single station persistent heavy rainfall had the largest range in June, and lasted 4 days at most. According to the second definition, the results show that the regional persistent heavy rainfall occurred in July frequently, and the characteristics of geographical distribution of regional persistent heavy rainfall were consistent with those the single station persistent heavy rainfall: the high incidence areas of the regional persistent heavy rainfall were in the western area of the basin and the northeastern hillside area of the basin. The regional persistent heavy rainfall occurred frequently after 2001, specifically the heavy rainfall events of lasting 3 days, but their strength reduced slightly.