A postural system for equestrian rehabilitation is provided that ensures correct positioning of the patient and correct passage of stimuli from the horse to the patient, even in the case of patients with severe motor disabilities. The postural system is modular and customizable and allows positioning the patient on the horse both in a sitting position and in a supine or prone position. The postural system comprises a base body and a plurality of shaped or shapeable blocks adapted to be removably connected to the base body and repositioned onto the base body. By selecting each time the number, shape and orientation of the shaped or shapeable blocks, it is possible to take into account the specific morphology of the user and facilitate perfect placement of the body and correct weight distribution.