To investigate the association of individual health behaviors with imune response against tumor or viral infection, peripheral blood lymphocytes of 185 healthy males in aged from 35 to 44 years for natural killer(NK) cell activity, frequencies of lymphocytes subsets and proliferation response of T and B cell. NK cell activity was determined by Cr release activity assay and lymphocytes subsets were counted using surface antigens(CD4, CD8, CD56) by flow cytometry. The responsiveness of T and B were measured as proliferation stimulated by mitogens. Subjects were classified into four distinct lifestyle patterns, health promotive lifestyle, passive lifestyle, fitness lifestyle and hedonic lifestyle from information on their health behaviors(cigarette smoking, alcohol consumption, and physical activity). Health promotive lifestyle had the highest NK cell activity(Lu30/10(6)CD56) which was significantly higher than hedonic lifestyle)p<0.05). The responsiveness of T cell was significantly lower in passive lifestyle and hedonic lifestyles compared to health promotive lifestyle and fitness lifestyles(p<0.05). However, there was no significant difference in the responsiveness of B cell, CD4, and CD8 among four lifestyles. This cross-sectional study showed the NK cell activity in individuals with desirable health behaviors was lower. The variation of immunity among individuals was not considered in this study, hence the intervention study reflection individual variations is recommended.