Abstract: Objective To investigate the prevalence of Ureaplasma ruealyticum(Uu),Mycoplasma hominis(Mh),Myoplasma genitalium(Mg),Myoplasma fermentas(Mf),Myoplasma penetrans(Mpe),and Myoplasma pirum(Mpe) infection and to explore the relation between mycoplasma infection and immune function among males with human immunodeficiency virus(HIV)infection.Methods A questionnaire survey was conducted to collect related information.The first void urine was collected to detcet Uu,Mh,Mg,Mf,Mpe,Mpi and venous blood samples were collected to measure peripheral blood T lymphocytes and Th1/Th2 cytokines.EXCEL and SPSS 11.5 were adopted in data analysis.Results The infection rates of Uu,Mh,Mg,Mf,Mpe,Mpi among the males were 51.7,34.0,29.0,6.6,1.6,and 16.3%, respectively,and the ratio of the males with CD4⁺ cells count less than 200/μL was 21.8% and 50.9% of the male with the count of CD4⁺ cells between 200 and 500/μL.Among the males,the median level(ng/mL)of interleukin-2,interleukin-4,interleukin-6,interleukin-10,interferon-γ,and tumor necrosis factor-α(TNF-α)was 145.059,1.315,0.420, 2.405,4.083,7.157,respectively.The levels of CD3⁺,CD4⁺,CD8⁺,and TNF-α of the males with AIDS-associated mycoplasmas infection were significantly lower than those of without the infection(U_CD3=2.86,P=0.004; U_CD4=2.73,P=0.006;U_CD8=2.40,P=0.017;U_TNF-α=2.71,P=0.007).Conclusion Infections of 6 pathogenic mycoplasmas exist among males with HIV infection and the infection may be associated with host immune function and should be concerned in clinical practice.