Paraneoplastic pemphigus (PNP) is a new variant with severe erosive lesions on the oral and ocular mucosaeand variable cutaneous lesions ; it resembles Stevens-Johnson syndrome. It is mainly associated with hematological malignant tumors, particularly non-Hodgkin’s B-cell lymphoma. The anti-keratinocyte cell surface IgG autoantibodies in the sera react predominantly with multiple plakin family proteins, suchas plectin, desmoplakins I/II, BP 230, envoplakin and periplakin, by either immunoprecipitation or immunoblot analysis. Desmogleins 3/1, which are antigens for classic types of pemphigus, are also involved in PNP. PNP is intractable to various treatments, and the prognosis is very poor. In addition, lethal respiratory conditions like bronchiolitis obliterans are frequently associated with PNP. Therefore, correct diagnosis in the early stages and proper treatments are extremely important for the management of PNP patients. Dermatologists must became very aware of the conditions of this life-threatening disease.