Using t he rainfall data of Sichuan-Chongqing regions at 160 stations of China and NCEP/NCAR data , t he relationship s between South Asia High and rainfall of Sichuan-Chongqing regions in July and August have been analysed. The results show that both had coincident periods , such as approximate 5-year time scales , approximate 10-year time scales. At approximate 5-year time scales , both the moving eastward of ridge line of SAH and variations of east basin of Sichuan-Chongqing had opposite phases ,SAH and rainfall of west basin had coincident phases before t he middle of 1990 , after lately 1990 , t heir phases were coincident . However , both SAH and rainfall of plateau of Sichuan had inconspicuous phases ,at inter-decadal time scales , three regions of Sichuan-Chongqing and moving eastward of ridge line of SAH had coincident phases , it was meaning that while SAH displayed East deviations , the trend about rainfall of Sichuan-Chongqing regions became increasing. Meanwhile , rainfall variations of Sichuan-Chongqing regions had dramatic relationship swith wind fields of SAH on 100 hPa , wind fields of Sichuan-Chongqing regions on 500 hPa and 700 hPa. In flood of east basin and drought of west basin year , the 16800 gpm line of SAH appeared the boundary position nearly of Sichuan and Chongqing. In flood of west basin and drought of east basin year , t he 16800 gpm line of SAH appeared west region nearly of Hubei province. Therefore , t he 16800 gpm line had well indicative meanings for rainfall of Sichuan-Chongqing regions when it librated in Sichuan province and Chongqing.