In the present report, we have analysed C.trachomatis infection and HIV positivity among patients (n-143) who attended the STD clinic at the Institute of STDs, Government General Hospital, Chennai. HIV positivity rate was significantly high among those with chlamydial infection than in those without chlamydial infection (29.5% (13/44) vs. 11.1% (11/99); p<0.05). The results of the present study suggest the association between C.trachomatis and HIV infections and reinforce the need for routine screening for C.trachomatis as a necessary intervention to reduce the burden of chlamydial diseases and to reduce the risk of HIV and its spread in India.