Objective To analyze causes of misdiagnosis of other related diseases as pigmented nevus,and to explore preventive measures so as to improve the clinical diagnosis.Methods A retrospective analysis was conducted on the clinical and pathological data of 140 cases which were selected from the pathological database of Xuancheng People's Hospital from Jan-uary 2019 to December 2022 and initially misdiagnosed as pigmented nevus before histopathological examination.Results Among the 140 cases clinically misdiagnosed as pigmented nevus,55 were males and 85 were females,aged 46.64±15.27 years.There were 55 cases of skin lesions on head,face and neck,44 cases on trunk,22 cases on limbs,13 cases on hands and feet,and 6 cases on vulva.Based on histopathological manifestation,70 cases were misdiagnosed with Seborrheic kerato-sis,9 with angiokeratoma,8 with basal-cell carcinoma,7 with cutaneous fibroma,6 with epidermis hemorrhage,4 with verru-ca vulgaris,4 with epidermoid cyst,3 with epidermal squamous cell hyperplasia,3 with soft fibroma,2 with actinic keratosis,2 with malignant melanoma,2 with sebaceous gland hyperplasia,2 with hair epithelioma,2 with syringoma,2 with calcified epithelioma and 14 with other skin diseases.Conclusion In clinical practice,many kinds of diseases are similar to pigmen-ted nevus and are more likely to be misdiagnosed.Combination of clinical features,dermatoscopic examination and skin histo-pathology can make definite diagnosis and improve the diagnostic rate.