Abstract: In this paper, we introduced the process of poisoning and diagnosis in two misdiagnosed cases of medicamentoselike dermatitis due to trichloroethylene. One patient was deceased after multiple referral treatments, the other recovered after seeking specialized consultation from centers for disease control and prevention and treatment in Yangpu District Central Hospital in Shanghai. The potential reasons of the misdiagnosis were:first, insufficient occupational prevention work and trainings; second, no symbolic symptoms of the dermatitis and subsequently delayed treatment; last but not the least, underestimate of the risky consequences of the disease which hindered the physicians following the principal of "early, sufficient, and gradual reduction" in dosage of applying glucocorticoids.