Abstract: Proposed is a modular augment, and, more specifically, a modular augment in which an additional unit is separably coupled to a center unit so as to selectively couple the additional unit to the center unit according to the degree of a patient's bone loss so that the degree of bone reinforcement can be easily adjusted, and thus a manufacturer is capable of covering various types of patients even though the types of units are minimized, thereby reducing manufacturing costs, the number of products to be prepared for surgery by a user such as a hospital is remarkably reduced, thereby preventing the unnecessary costs and facilitating inventory management, and a patient can receive an optimal augment that is appropriate for the patient' condition.