Abstract: Based on 850-hPa geopotential height field at 6-hour intervals extracted from the ERA-Interim reanalysis data during 1979-2013, cyclones that affected over the Yangtzi-Huaihe River valleys (YHV) in the spring were detected by using the 2D cyclone area objective identification method, which can detect the outermost enclosed contour of the cyclone. The spatial-temporal characteristics of synoptic-scale cyclones and their relationship with regional precipitation anomalies in the spring over the YHV were investigated. The results show that the inter-annual variation of synoptic-scale cyclone activities displays a significant positive correlation with precipitation anomalies as well as the occurrence frequency of heavy precipitation over the YHV. A significant quasi-barotropic high-pressure center exists in northeastern Asia when the cyclone activity intensifies, which is mainly induced by the upper troposphere warming that weakens the meridional temperature gradient to the south of Japan. Such a circulation configuration is conducive to the decrease in the upper westerly jet and positive vorticity advection in the northern part of the YHV, which are accompanied by anomalous southwesterlies in the middle and lower troposphere in the south of YHV. The horizontal trough and cyclonic circulation anomalies in the YHV result in increased vorticity over this area. The associated low-level convergence and high-level divergence provide a favorable dynamic lifting condition for the development and maintenance of synoptic scale cyclone in the YHV. The abnormal circulation configuration of the lower level horizontal trough is favorable for the intensification of warm, moist southwesterly flow in South China and anomalous easterly/southeasterly flow in northern YHV, and thus leads to increases in regional cloud cover and precipitation anomalies.