Abstract: Seroepidemiological study of spotted fever group rickettsiae infection was carried out in 1012 healthy persons in three counties of Guangdong Province by method of microimmunofluorescence assay. The results showed that the prevalence rates of antibody of R. sibirica was 28.47%、20.46% and 6.8% in Dapu, Pingyuan and Mei Counties respectively; that of R.conorii were 27.78%、 13.42% and 25.59% respectively and of R.akari were 21.88%、 18.80% 、 15.49% respectively . The highest antibody prevalence (28.47%) was found in Dapu County. Prevalence rates of antibodys were not correlated with sex、age and profession.