Abstract: In this paper, the results of IL-2 production and NK activity of peripheral blood mononuclear cells (PBMC) from 34 patients with herpes zoster (HZ) and 30 normal donors and the observation of IL-2 level between acute and recovery phase from 11 patients with HZ are reported. The results indicated that IL-2 level of PBMC from patients with HZ decreased significantly when compared to normal donors (P<0.01). By contrast, there was no difference between the patients and healthy group in NK activity (P>0.05), and the difference of IL-2 level between acute and recovery phase of 11 patients with HZ was not significant (P>0.05). According to these results, the authors suggest that the diminished IL-2 production may play a role in the development of HZ, and postulate that it is of benefit to treat HZ by using exogeneous IL-2 or raising IL-2 production in vivo.