Kaposi's sarcoma is the most common malignant lesion in patients who test seropositive for the human immunodeficiency virus. Although many cases of this tumor have been described in the literature, only a few cases have been related to Koebner's phenomenon following trauma. Biopsy of lesions remains the standard method of diagnosis, but the numerous treatment options available today require treatment to be determined on a case-by-case basis. The authors present an unusual case of trauma-induced, acquired immunodeficiency syndrome-related Kaposi's sarcoma of the hallux with successful treatment through radiotherapy.