Atrophy of the alveolar ridge requires bone grafting at the implant site for rehabilitation of the masticatory function with dental implants. Despite the advances in the development of bone substitutes, autogenous bone graft remains the "criterion standard" because of its osteogenic, osteoinductive, osteoconductive potential, and non-immunogenic properties. However, harvesting of autogenous bone is not exempt from donor site morbidity. In this context, the use of autogenous bone derived from the proximal ulna might be a viable resource to obtain corticocancellous bone graft, as the harvesting from this donor site is associated with low morbidity. Thus, this article aimed to describe a case in which a maxillary sinus floor augmentation was performed by means of autogenous bone graft harvested from the proximal ulna, as the donor site. An appositional bone block graft harvested from the same region was used to augment the residual alveolar ridge. Clinically, healing proceeded uneventfully with no major complications. After 8 months, a proper amount of bone was found at the implant site, allowing a prosthetically driven implant insertion and subsequent implant-supported rehabilitation. Results were clinically and radiographically stable after a 3-year follow-up. The present case report suggested that proximal ulna as a donor site should be considered as a safe and reliable alternative for alveolar ridge augmentation. Besides the case presentation, a comprehensive review of the literature was also provided.