Abstract: Objective This study was conducted to investigate the Mycoplasma genitalium(Mg)infections among STD patients in Jiangmen City for the prevention and control of sexually-transmitted diseases. Methods 84 STD clinic patients' genitourinary tract secretions were collected for Mg DNA detection by polymerase chain reaction (PCR). Results The Mg DNA positive rate of STD clinic patients was 17.86%, males' and females' positive rates being 21.21% and 5.56%, respectively, between which was no statistical significance ( 2=1.42, P﹥0.05).The sensitivity of PCR detection for the Mg standard strain(G37) was 10 ccu/ml. No cross reaction between other 10 mycoplasmas and 10 relative microorganisms was found. Conclusion Mg infection was found commonly among STD patients in Jiangmen City, which deserves precautions in disease protection and control.