The purposes of this study were investigated physical compensation for gait on induced knee stiffness in normal subjects. Ten subjects were participated in the experiment(age: $26.0{pm}6.3$ yrs, height: $175.5{pm}5.3$ cm, weight: $69.1{pm}6.1$ kg). The study method adopted 3D analysis with five cameras and ground reaction force with two force-plate. Induced knee stiffness level were classified as gait pattern on ROM of knee(free level, $30^{circ}$ restriction level, fix level). The results were as follows; In angular displacement of hip joint, left hip joint was the more extended in mid-stance on induced right knee stiffness. In angular displacement of knee joint, there was no physical compensation on induced right knee stiffness, but free knee level gait was more flexed in swing phase of right knee joint. In angular displacement of ankle joint, right ankle joint was the more dorsiflexed on induced right knee stiffness, and $30^{circ}$ restriction level and fix level gait were less plantarflexed in TO2. In trunk tilt, free and $30^{circ}$ restriction level gait was more backward tilt on induced right knee stiffness. In ROM of each joint, right knee joint was more larger and trunk tilt was more lower on induced right knee stiffness. In GRF, Fx was more bigger lateral force in free and $30^{circ}$ restriction level gait, and was more bigger medial force in fix level gait. Fy was more bigger propulsion force in free level gait, and was was more bigger braking force in $30^{circ}$ restriction level gait. Left braking force in $30^{circ}$ restriction level gait was more bigger. Fz was no significant.