A case of contact dermatitis due to herb onintment is described in a 24 year-old female patient. After topical application of herb ointment, she developed erythematous papules and plaques on the face and neck. Patch test revealed positive reactions to ammoniated mercury, thimerosal, and the herb ointment. Energy-dispersive X-ray microanalysis of the herb ointment showed a striking peak for mercury. (Kor J Dermatol 28(2): 212 215, 1990)