Abstract: Objective Monitoring data of hemorrhagic fever with renal syndrome from 2001 to 2003 in Zhejiang Province were analyzed so as to provide scientific basis for the implementation of preventive measures against renal syndrome. Methods Descriptive epidemiological approaches were used to ana lyze the epidemic and investigate host animals：Direct immunofluorescence assay(FA)was adopted to determine HFRS antigen and indirect immunofluorescence assay(IFA)was used to determine specific IgG antibody. Results Within these 3 years，there were totally 4 240 eases of HFRS in the whole province with 19 cases of death and an incidence of 3.12／lakh and mortality of 0.45％，of which com-pared with 2002，the onsets and death cases of 2003 declined by 36.76％and 50.00％：the onsets of 2002 decreased by 24％ compared with 2001. Throughout the whole province，the onset of HFRS still displayed a relatively convergent and stabilized trait，primarily distributed among eastern and western bighlands of Zhejiang along Qiantangjiang coast and southern mountainous area，Shaoxing，Ningbo and Taizhou were cities that HFRS occurred most frequently，accounting for 56.3％ of the total.This dis ease occurred around the year with May to July(1 276 cases)and November to January of the next year (1 341 cases)as predominating periods，accounting for 30.1％and 31.6％，respectively. People aged between 20 and 50 years old were most easily affected，accounting for 68.3％ of the total cases.As for occupation，farmers were the majority with a rate of 79.3％. The ratio of male to female was 2.5：1 The coincidence rate of clinical diagnosis in cases was 82.51％：the recessive infection rate of healthy population was 2.04％. The serological positive rate of mice was 11.76％：that of ducks was 23.26％ Apodemus agrarius was the predominating species in the wild followed by brown rattus：Indoors，brown rattus was predominating. The virulence carriage rate of rat lungs was 15.55％.Conclusion The vir-ulence carriage rate of host animals ls relatively high and surveillance should be further strengthened.