Abstract: Natural villages on the shore of the Taihu Lake in Yixing were selected as objects in the study. Rainfall and pollutants in the rainfall-triggered runoff from 4 different types of underlying surface (roof, courtyard, road and private plot) were monitored and event mean concentrations (EMC) of the pollutants were calculated so as to explore characteristics of the release of pollutants with runoff from different types of underlying surface under natural rainfalls and simulated rainfalls and their affecting factors. Results show that the runoffs were seriously polluted regardless of type of underlying surface, and direct discharge of the runoff into receptor waterbodies would cause serious environment pollution. EMC of COD, SS, TN and TP in the runoff from 4 different types of underlying surface after each natural and simulated rainfall event varied in the range of 52.77-133.94, 55.02-935.65, 2.20-8.59 and 0.066-2.96 mg·L^-1, respectively. Among 4 types of interlying surface, private plot was the highest in all the pollution indices. Rainfall and rainfall intensity were the two important factors affecting COD and SS concentrations in the rural runoff, EMCs of the pollutants in runoffs from courtyard, road and private plot, were positively related to the number of sunny days prior to the start of rainfall events, but EMCs of the pollutants in runoffs from roof were not significantly related.