Objective: To observe the effect of immunoglobulin in the adjuvant therapy of viral meningoencephalitis (VM). Methods: A total of 78 cases of VN in our hospital from September 2011 to April 2016 were chosen. According to the admission order, they were randomly divided into two groups, the control group and observation group, and 39 cases in each group. The control group was treated with acyclovir conventional therapy, and the observation group was supplemented by immunoglobulins. The differences of serum and cerebrospinal fluid levels of T cell subsets and inflammatory cytokines between the two groups before and after treatment were compared. Results: The total effective rate of the observation group was significantly higher than that in the control group (P<0.05). The serum and cerebrospinal fluid levels of T cell subsets CD3+ , CD4+ and CD4+ /CD8+ were significantly higher than those in the control group, while the CD8+ was lower than that in the control group (P<0.05). The serum and cerebrospinal fluid levels of inflammatory cytokines PCT, INF-γ, IL-6 and TNF-α were all significantly lower than those in the control group (P<0.05). Conclusions: Immunoglobulin can effectively improve the level of CD3+ , CD4+ and VM in CD8 patients, and adjust the CD4/CD8 balance, inhibit synthesis and secretion of Th1cytokines, so to play the assistant effects of acyclovir in the treatment of VM.