A customizable seating structure, designed to be connected to a movable or stationary frame. The structure comprises a seat element (2) which has a top surface, designed to at least partly contact a user, and a support element (4) underlying the seat element (2) and designed to be connected to the movable or stationary frame (T). The seat element (2) is removably attached to said support element (4) to allow removal and/or replacement thereof by a user. The seat element (2) is attached to the support element (4) by screws (7) and nuts (9) or press-fit of pins (13) in holes (8). The seat element (2) is composed of a resilient upper body (15) removably connected to a semirigid lower body (16).