We examined how age affects how postural strategies change as perturbation magnitude changes. Previous studies showed that young adults continuously scale postural response gains from ankle strategy to more and more hip strategy with increasing biomechanical constraints but it is now known whether elderly subjects show the same scaling (Park et al.,2004). Postural responses were analyzed with full-state feedback control whose gain parameters characterize the response of each group. The gain scaling indicates that the elderly relies more on hip strategy, while the young continuously changes from ankle to hip with perturbation magnitude.