Abstract: Based on the China daily rainfall data and the NCEP/NCAR reanalysis data in 1961-2010, the influence of decadal change of the large-scale circulation on persistent torrential precipitation (PTP) in the different frequent periods over South China has been explored. The results show that during the two periods with frequent persistent torrential precipitation events (from the mid-1960s to mid-1970s and from the 1990s to around 2010) in the past 50 years although the occurrence of persistent torrential precipitation is generally accompanied by the cold air from the middle-high latitudes and sufficient vapor supply from the low latitudes, the large-scale circulation in the different periods show obvious difference. Therefore, the characteristics of persistent torrential precipitation in the two periods are different. In the recent twenty years, persistent torrential precipitation occurs more frequently and its intensity is stronger. During the persistent torrential precipitation active period in 1964-1976, the cold air originated from the front part of a wide low trough in West Siberia while water vapor came from the India-Burma trough in the Bay of Bengal. Meanwhile, the western North Pacific high was weak and shifts eastward, and the South Asian high was weak as well. Precipitable water was not more than normal, but the vertical velocity and vapor convergence was strong, resulting in a quite stable background over South China. Whereas during the persistent torrential precipitation active period from the 1990s to 2010s, cold air was from the back of the active high pressure ride over Okhotsk Sea, and the western North Pacific high is strong and shifts westward, which enhanced water vapor transport into South China from its northwest side. Meanwhile, the strong South Asian high provided upper-level divergence over South China, which enhanced vertical ascending motion, vapor convergence and sufficient precipitable water, and persistent torrential precipitation intensity is stronger and its influence areas are wider during this period. These features suggest that the decadal adjustment of the large-scale circulation can lead to decadal change of persistent torrential precipitation, and the influence of decadal variation of climate background on persistent torrential precipitation should be considered in making the relevant prediction.