Introduction We described the dynamic effects of traction on the radiolunate and capitolunate joints in a living body to explore the possibility of range of motion exercise of the wrist joint under traction as a new method of exercise. Methods Dynamic radiography was conducted while creating wrist passive movements by using manual traction and machinery traction with a measurement device. Subjects were 20 healthy men. The change in the percentage of contribution of the radiolunate and capitolunate joints with or without traction was calculated. Results Manual traction: During palmar flexion, the percentage of contribution of the radiolunate angle was increased from 39.4% to 49.9%, and the capitolunate angle was decreased from 60.6% to 50.1% with traction. During dorsiflexion, the radiolunate angle was increased from 60.2% to 70.0%, and the capitolunate angle was decreased from 39.8% to 30.0% with traction. Machinery traction: During palmar flexion, the radiolunate angle was increased from 46.1% to 56.4%, and the capitolunate angle was decreased from 53.9% to 43.6% with traction. During dorsiflexion, the radiolunate angle was increased from 68.7% to 72.0%, and the capitolunate angle was decreased from 31.3% to 28.0% with traction. Conclusions The movement of the radiolunate joint was increased and that of the capitolunate joint decreased with the addition of traction. Range of motion exercise with traction has the potential to be applied to an advanced rehabilitation program targeting the radiolunate joint under specific pathological conditions.