Using the daily National Centers for Environmental Prediction (NCEP) global final analysis (FNL) data and daily station rainfall data in China for the winters of 2000-2011, we first define an index to measure the strength of the South China quasi-stationary front (SCSF), and strong SCSF cases are then selected. The structure and characteristic circulation of strong SCSFs in relation to winter precipitation over South China are analyzed by composite analysis. The results show that strong SCSFs are nearly west-east oriented, are more common in January and February, and their frequency of occurrence shows a clear upward trend over the past 12 winters. The frontal zone of a strong SCSF is indicated by a dense band of potential pseudo-equivalent temperatures in the lower troposphere, slanting northward with altitude, with obvious differences across the band in temperature rather than in moisture. In addition, the frontal zone is often associated with a great temperature inversion, positive relative vorticity, and moisture flux convergence of north and south winds. Updrafts mainly appear above the slanted frontal zone, and disturbance zonal circulations with sub-frontal scale updrafts and downdrafts exist at about 850 hPa below the upper-level westerlies. Strong SCSFs can be classified into three types according to their wind convergence patterns in the frontal zone at 850 hPa. Among these three styles, the northerly convergence type is characterized by stronger cold air from the north and less precipitation in South China; the southerly convergence type features strong south winds, a deeper India-Burma trough, and more precipitation in South China; and the northerly and southerly convergence type falls in between these two. Winter rainfall in South China is closely related to a winter SCSF. In the presence of strong SCSFs, stronger moisture flux convergence and an enhanced ascending motion appear in the lower frontal zone over South China, accompanied by a deeper India-Burma trough in the mid troposphere to the west of the SCSF, leading to increased rainfall in South China.