In a patient with both lichen planus and psoriasis, and suffering from hepatitis C virus infection, we examined the T cell receptor (TCR) Vb repertoire by reverse transcriptase polymerase chain reaction in skin lesions from psoriasis and lichen planus. A variety of rearranged variable TCR genes was found in the skin lesions, and the TCR Vb repertoire of the infiltrating T cells was not restricted. Although different patterns of expression were observed in the two lesions, TCR Vb 2 and 7 were commonly found.