After transplantation, the main concerns involve immunosuppression, the prevention and treatment of infections and graft rejection, and tumor prevention. Sometimes the complications that may appear in the arteriovenous fistula are neglected following kidney transplantation. This is the reason why we are presenting the case of an angiosarcoma developing in an arteriovenous fistula after kidney transplantation. It is a very rare case and our goal is to create an alarm so that after kidney transplantation clinicians do not lose sight of the patients' previous history.