Objective To investigate the effect of fungus Aspergillus fumigatus and Candida albicans on the expression of endocellular interferon-γ (IFN-γ) and interleukin-4 (IL-4) in cytokineinduced natural killer (NK) cells.Methods NK cells were cultured with Aspergillusfumigatus or Candida albicans by non-contact or direct-contact methods with a ratio of NK cells to fungus of 10 ∶ 1.The expressions of IFN-γ and IL-4 in NK cells were evaluated by flow cytometry after co-cultured for 6 h.Analysis of variance or SNK-q test was used to compare the expressions of IFN-γ and IL-4 among different groups.Results The IFN-γexpression rates in NK cells with direct contacting to Aspergillus fumigatus hyphae,or to different morphotypes of Candida albicans were (20.12 ± 0.53) ％,(20.69 ± 0.34) ％ and (20.8 ±0.37)％ respectively,while IFN-γexpression in NK cells with indirect contacting to fumigatus hyphae,or to different morphotypes of Candida albicans were (21.40 ± 0.53) ％,(20.57 ± 1.09) ％ and (20.20 ±0.51) ％ respectively,and all were significantly higher than that in the blank group [(15.11 ± 2.60) ％,all P ＞ 0.05].The IFN-γ expression rates in the Aspergillus fumigatus spores direct and indirect contacting groups were (14.33 ± 0.98) ％ and (14.97 ± 1.53) ％,which were not of significant difference compared with the blank group (P ＞ 0.05).The IL-4 expression rates in NK cells with direct contacting to different morphotypes of Aspergillus fumigatus and Candida albicans were (1.25 ± 0.06) ％,(1.21 ± 0.03) ％,(1.22 ± 0.46) ％ and (1.26 ± 0.11) ％,while those in indirect contacting groups were (1.21 ± 0.06) ％,(1.25 ±0.04)％,(1.27 ±0.03)％ and (1.26 ±0.1)％,which were not of significant difference compared with the blank group [(1.23 ± 0.05) ％,all P ＞ 0.05].Conclusion Fungus stimuli can reduce the secretion of IFN-γ in NK cells,but have not significant influence on the secretion of IL-4.