The presence of macroglossia, a tendency towards poor cooperation and the inability to adapt to compl~te dental prostheses due to motor and mental deficiencies makes the oral rehabilitation of Down Syndrome patients difficult. This article reports on the use of mini implant supported overdenture to rehabilitate a Down Syndrome patient who had difficulty adapting to his new mandibular complete denture. The patient's ability to cooperate during treatment as well as the maintenance of an optimal oral hygiene practice enabled mini-implants to be inserted and maintained 20 months post insertion as evidenced by clinical and radiological findings. To the author's knowledge, this is the first reporting of a successful mini implant supported overdenture in a Down Syndrome patient.