Despite the fact that benign skin lesions can undergo malignant transformation, the necessity and timing of the surgical resection have yet to be established. In this study, we analyse three cases of benign-appearing skin lesions, which were found to be carcinomatous on histologic examination and review the literature regarding the importance of prophylactic removal of benign-appearing skin lesion. The first and second cases were female patients wishing for cosmetic surgery. The first patient had a benign-appearing lesion on dorsum nasi, and the second patient had an inconspicuous lesion right along the right nasolabial fold. The third patient was a middle-aged male with a pigmented lesion on the left cheek, who presented to the clinic only after having met the operating surgeon through an acquaintance outside the hospital setting. All of the lesions were suspected to be of benign nature and were excised for cosmesis only. However, histologic examination of these lesions showed that the first two tumors were basal cell carcinoma with the last tumor being squamouse cell carcinoma. Thus, it is considered that removal of benign like skin lesion will result in good prognosis of patients scheduled to undergo other surgery.