Objective To study the profile of peripheral natural killer cells(NK cells)and γδT lymphocytes in human immunodeficiency virus(HIV)infected patients with different disease status and to explore the pathogenesis of acquired immunodeficiency syndrome(AIDS).Methods Three hundred and eleven HIV/AIDS patients without antiviral treatment were enrolled in this study.The percentages and absolute numbers of CD4+T lymphocytes,NK cells,and γδT ceils were measured by flow cytometry.The patients were divided into 3 groups based to their CD4+T lymphocytes counts:low CD4+T lymphocytes group(L),patients with CD4+T lymphocytes <0.20×109L;middle CD4+T lymphocytes group(M),CD4+T lymphocytes counts between 0.20×109and 0.35×109L;high CD4+T lymphocytes group(H),patients with CD4+T lymphocytes counts >0.35×109L.Rank sum test of independent samples of two-group and multiple-group was performed using Mann-Whitney U test and Kruskal-Wallis test.Correlation analysis was done by Spearman and Pearson test. Results The median percentage and cell counts of NK cells(8.4%,103×106L) and γδT cells(3.4%,41×106L)in HIV/AIDS patients were all significantly lower than those of healthy individuals(Z=-5.029,Z=-7.723,Z=-2.437,Z=-6.063;all P<0.01).The median cell counts of CD4+T lymphocytes in L,M,H groups were 0.062×109L,0.276×109L and 0.482×109L,respectively.The median cell counts of NK cells in these 3 groups were 89×106L,97×106L and 146×106L,respectively.NK cell counts were not significantly different between L and M groups,whereas both of them were much lower than that of H group(Z=-3.392,P=-0.001,Z=-4.849,P<0.01,respectively).The median γδT cell counts of L,M and H group were 29×106L,43×106L and 59×106L,respectively.The differences between any 2 groups were not significant.Conclusion These data suggest that the decreasing levels of peripheral NK cells and γδT cells are different after HIV infection.