Abstract: The effect of topical application of tincture of Anglica dahurica and subsequent exposure to long-wave ultraviolet rays on the induction and elicitation of contact sensitivity to dini-trochlorobenzene (DNCB) in guinea pigs was studied. The number of ATPase positive cells decreased significantly after Angelica dahurica and UVA irradiation, and the residual Langerhans cells seen in the treated skin area exhibited morphological changes. When subery-thema dose of Angelica dahurca and UVA was given at the induction site for 6 days prior to sensitization, the challenge reaction at no-nirradiated skin area was not evidently affected as compared to control animals.