Abstract: Objective This study was done to get an insight into the influence of flood and waterlog ging disasters on the epidemiological faclors of leptospirosis and its effective prevention and treatment strategies Methods Techniques of epidemiological investigation were applied to study the influence of flood and waterlogging disasters on the epidemiological factors of haman leptospirosis in Gongan county Results Statistics sDowed that the mean annual incidence of leptospirosis from 1990 to 2000 in Gongan county was 7.99/100,000，with the epidemic mainly occurring in July and August Bacterial culture of 53 mouSe arid 168 swine kidneys was negative，bot PCR detection revealed positive findings for bacteria in 6 mouse kidneys(positive rate，11.32％) and in 1 swine kidney (positive rate，0.59％)，with a higher carrier rate in mice than in pigs. The mean antibody against L interohaemorrhagiae for health people was 0.048μg/μl，showing no difference with that of L.pomona，while the mean antibody against L.grippolyphsa was 0.056μg/μl it was showed that inoculation of bacterial vaccine of leptospirosis was able to effectively prevent lepltospirosis No significant correlation was fomld from the single faclor analy sls of the incidence of leptospirosis and the rainfalls，the air temperatures and the water levels of Yangtze River from 1999 to 2000 in Gongan county Conclusion Flood and waterlogging disasters have some in fluence on the prevalence of leplospirosis but are not determinant factors Comprehensive strategies for the prevention and control of leptospirosis include the control of source of infection，health education and irinocullation of leptospirosis vaccine