OBJECTIVETo study the regulatory effect of Qinghuo Baidu Yin (QHBDY, a mixture prepared with Chinese drugs) on immune function of patients with extremely severe burn (ESB).METHODSThirty patients with ESB were divided into two groups, conventional therapy was given to both groups, but QHBDY was given to the treated group additionally. Immunological indices, including peripheral blood T-lymphocyte subsets, immunoglobin (IgG, IgA and IgM) and complement (C3 and C4) were determined 3 weeks after treatment to evaluate and compare the therapeutical effect in the two groups.RESULTSCompared with the control group, CD3, CD4, CD4/CD8, immunoglobin (IgG, IgA and IgM) and complement (C3 and C4) levels were markedly decreased in degree, and recovered earlier and quicker, with CD8 increased mildly (P < 0.01) and turned back more quickly. And so did the parameters of the treated group in comparing with that of the control group at anytime (P < 0.05 or P < 0.01).CONCLUSIONChinese drugs mixture shows the regulatory effect on both cellular and humoral immune function in patients with ESB.