ObjectiveTo analyze the contact allergens of melanosis. MethodsFifty-six patients confirmed with melanosis between June 2010 and October 2013 received patch test and BICOM test, and the results were analyzed statistically and clinical data of the included patients were retrospectively analyzed. ResultsOf the 56 patients, 50 patch tests and 40 BICOM tests were positive. The top three chemical allergic resources in patch test of these patients were nickel sulfate (33.9%), aluminum (21.4%), and potassium dichromate (16.1%). The positive rates of male patients with aluminum, rubber compounds and cobalt chloride were significantly higher than those of females. The positive rate of female patients with nickel sulfate was significantly higher than that of males. The differences were all significant (P＜0.05) . ConclusionNickel sulfate, aluminum and potassium dichromate may be the main allergens of melanosis.