Based on ERA-Interim reanalysis data of four times a day provided by ECMWF and daily precipitation data from 753 stations provided by China Meteorological Administration, the characteristics of summer precipitation in Yangtze-Huaihe river basin from 1980 to 2013 are analyzed. The forecast signal of summer low-frequency precipitation in Yangtze-Huaihe river basin is explored. The results show that: 1) The 10-30 days low frequency precipitation which occupies a large proportion in the summer precipitation can influence the summer precipitation over the Yangtze-Huaihe river basin. 2) At 200hPa, there is a low-frequency anticyclone moving from the northeast of the Tibetan Plateau to the eastern China in 9-6 day before the low-frequency precipitation process occurred. At 500hPa, the Western Pacific Subtropical High moved from east to west reaches the eastern coastal areas of China during 9 days before the occurrence of low-frequency precipitation process. The center of negative low frequency OLR in the tropics moves northward and reaches the strongest when its northernmost reaches the Yangtze-Huaihe river basin. The above circulation distribution will promote the occurrence of the low-frequency precipitation in the Yangtze-Huaihe river basin, or the vice versa. 3) The Tibetan Plateau prediction signal can effectively supplement the deficiency of the West Pacific Subtropical High and the tropical OLR signal. The accuracy of precipitation process prediction relying only on the low latitude signals can be improved by using the Tibetan Plateau Signal, Western Pacific Subtropical High Signal and Tropical OLR Signal as comprehensive predictors.