Objective : This study obtained normative values for variable parameters of lumbar function with the isoinertial triaxial dynamometer in patients with chronic low back pain. Subjects and Methods : 30 patients(male 15, female 15) with chronic low back pain in this study. Variable parameters that were measured with the Isostation B-200 were lumbar range of motion, isometric maximum torques, and maximum velocities in three axis. Results : In patient male group mean R.O.M. was $82.9{pm}12.5$ degrees in lumbar rotation, $76.5{pm}17.1$ degrees in lumbar flexion/extension, and $64.3{pm}14.5$ degrees in lumbar lateral flexion. In patient female group mean R.O.M. was $78.4{pm}18.5$ degrees in lumbar rotation, $71.7{pm}20.4$ degrees in lumbar flexion/extension, and $63.2{pm}14.4$ degrees in lumbar lateral flexion. In patient male group mean isometric maximum torques was $64.7{pm}23.8ft-lbs$ in lumbar rotation, $81.1{pm}42.0ft-lbs$ in lumbar flexion, $122.2{pm}43.6ft-lbs$ in lumbar extension, and $101.0{pm}37.0ft-lbs$ in lumbar lateral flexion. In patient female group mean isometric maximum torques was $41.9{pm}9.2ft-lbs$ in lumbar rotation, $49.9{pm}23.9ft-lbs$ in lumbar flexion, $90.1{pm}26.8ft-lbs$ in lumbar extension, and $62.0{pm}16.7ft-lbs$ in lumbar lateral flexion. In patient male group mean maximum velocity of isoinertial exercise with low (25%) resistance was $102.4{pm}28.8deg/sec$ in lumbar rotation, $108.9{pm}32.2deg/sec$ in lumbar flexion/extension, and $103.5{pm}30.4deg/sec$ in lumbar lateral flexion. In patient female group mean maximum velocity of isoinertial exercise with low (25%) resistance was $84.1{pm}24.4deg/sec$ in lumbar rotation, $93.2{pm}32.9deg/sec$ in lumbar flexion/extension, and $98.5{pm}33.7deg/sec$ in lumbar lateral flexion. In patient male group mean maximum velocity of isoinertial exercise with high (50%) resistance was $74.0{pm}20.9deg/sec$ in lumbar rotation, $98.7{pm}32.8deg/sec$ in lumbar flexion/extension, and $85.0{pm}25.8deg/sec$ in lumbar lateral flexion. In patient female group mean maximum velocity of isoinertial exercise with high (50%) resistance was $67.3{pm}26.4deg/sec$ in lumbar rotation, $82.5{pm}31.0deg/sec$ in lumbar flexion/extension, and $79.7{pm}23.9deg/sec$ in lumbar lateral flexion. Conclusion : Maximum isoinertial velocities were more reliable and more significant than isometric maximum torque for the objective assessment of chronic low hack pain.