Human joint motion measurement means a lot in judicial expertise, rehabilitation medicine and other fields. This paper designs and realizes a kind of joint motion measurement system based on euler angle. The System get marker location information through optical positioning device, then compute angles using algorithm of rotation matrix and euler angle inverse solution.System has realized the accurate, realtime motion measurement and it suit to the motion measurement of neck, waist, shoulder, elbow, wrist, hip, knee and ankle. Accuracy verification experiment show that the system precision can reach within 0.3 degrees.