Objective:To analyze the characteristics of immune status in patients with different types of oral lichen planus(OLP). Methods:197 cases of OLP,61 with reticular OLP(ROLP)and 136 with hyperaemia erosion OLP(HEOLP)were included.The im-mune status of the patients were investigated by flow cytometry (FCM)for the expression of CD3 +,CD4 +,CD8 +,CD19 +,CD16 ++56 +and CD4 +/CD8 +cells,and nephelometry for the measurements of IgG,IgA,IgM,C3 and CH50 in peripheral blood.The la-brotary norm was used as the reference and the characteristics of immune status in patients with different clinical characters of OLP were analyzed by SPSS 16.0.Results:CD3 +,CD4 +,IgA and C3 decreased,CD19 +cells,IgG,IgMand CH50 increased in patients with OLP.CD16 ++56 +,CD4 +/CD8 +cells decreased in the cases with ROLP(P<0.05);CD8 +cells decreased in the cases with HE-OLP.CD3 +,CD8 +cells were fewer in HEOLP patients than that in ROLP,CD4 +/CD8 +cells were more in HEOLP than that in ROLP(P<0.05).Conclusion:There are defects of cellular immune function and increase of humoral immune in patients with OLP. The patients with different clinical types of OLP may have different immune fuction changes.