Immunotherapy represented by PD-1/PD-L1 inhibitors has become the main treatment of malignant tumors. However,the adverse events caused by immunotherapy can not be ignored. Among them,dermatological immune-related adverse events （irAEs） occur with the highest incidence. Most dermatological irAEs belong to grade Ⅰ-Ⅱ, which does not affect the application of PD-1/PD-L1 inhibitors. The pathogenesis of dermatological irAEs is not fully understood. The most common types of dermatological irAEs are rash,pruritus and vitiligo. The domestic PD-1 inhibitor camrelizumab has unique adverse reactions of reactive cutaneous capillary endothelia proliferation （RCCEP）. It is found that dermatological irAEs can predict the clinical efficacy of PD-1/PD-L1 inhibitors in patients with malignant melanoma and non-small cell lung cancer （NSCLC）,especially RCCEP can be used as a potential biomarker of the efficacy of camrelizumab in the treatment of NSCLC, hepatocarcinoma, and esophageal cancer.