Subungual melanoma typically presents with dark, longitudinal lines under the fingernail. The disease is commonly initially misdiagnosed, which leads to delays in correct diagnosis and treatment. Diagnosis is especially difficult in the case of amelanotic subungual melanoma. A histopathological diagnosis is essential; therefore a nail matrix biopsy must be performed. Surgical treatment includes amputation of the distal phalanx of the involved finger. Current data show that amputation higher than the proximal interphalangeal joint does not improve survival. Wide en bloc excision is a less invasive method of treating in situ subungual melanoma. Five-year survival in patients with stage I subungual melanoma is 74% and in patients with stage II 40%. In the following report, we present a case of subungual melanoma in an 89-year-old patient. Since more than a year had passed until the correct diagnosis was made, we would like to emphasize the importance of a timely diagnosis. We believe all lesions with delayed or improper healing of the nail matrix after ablation demand a dermatoscopic examination or an excision biopsy of the nail matrix. In case of a histopathological diagnosis of subungual melanoma, the patient needs an immediate referral to a surgical oncologist.