A total of 875 serum samples from dairy cattle in six districts in Zhuang Autonomous Region (GZAR) were collected between June 2009 to March 2010, and Chlamydia antibodies were assayed by indirect hemagglutination test (IHA). The overall seroprevalence of Chlamydia in dairy cattle was 17.83% (156/875) in GZAR. The seroprevalence of Chlamydia in aborting dairy cattle (18.18%) was higher than that in non-aborting dairy cattle (16.69%) (not statistically significant). Dairy cattle of seven year

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... had the highest seroprevalence (35.42%), and dairy cattle with seven calves had the highest positive level (100%, 1/1). Statistically significant differences were observed between Chlamydia prevalence and ages (P<0.05), especially in dairy cattle of 5 to 7 year old (P<0.01). Moreover, statistically marked differences were also found between Chlamydia prevalence and numbers of pregnancies (P<0.01). These results indicated that infection of Chlamydia in dairy cattle is widespread in GZAR and is closely related to abortion of dairy cattle, therefore integrated strategies should be carried out to prevent the outbreak of Chlamydia infection.