Pigmented photoallergic contact dermatitis is a disease usually resulting from recurrent cutaneous exposure to cosmetic photoallergens which produce bizarre dark brown hyperpigmentation. Histologicnl examination of this condition reveals liquefaction of the basal cells of the epidmis and melanophages in the upper dermis. A 50-year-female developed dark brownish mottled hyperpigmented patches on her face after using a soap named O.E. and taking a nap every afternoon for 4 years. The histological fmding on the lesion site was consistent with pigmented photoallergic contact dermatitis. The cosmetic photopatch test with, O.E. soap, and the Scandinavian scries resulted in a positive reaction only on one side where 5 J/cm2 lights were applied by using Waldman 800UV machine. The other side howed a negative finding. We fmally diagnosed pigmented photoallergic contact dermatitis based on the patients histoty of using the soap containing musk ambrette, a histological examination of a biopsy and the results of photopatch tests. We report rare case of pigmented photoallergic contact dermatitis. (Korean J Dermatol 1998;36(5): 938-941)