Two independent station networks are selected in South China.The low-density one includes 15 stations,while the high-density one contains 42 stations.The similarities and differences of precipitation fields of the pre-flood season of South China obtained from the two networks are analyzed based on their May-June daily precipitation data from 1958 to 2000.Statistical results show that:1)the regionally averaged precipitation of the seasonal andmonthly scales obtained from the two networks has no notable difference,but one of pentadly and daily scales has;2)both the daily climatologicalmean and anomaly fields obtained from the two station networks have notable differences.