Provided is a running form diagnostic system with which it is possible to automatically score a runner's running form. The running form diagnostic system acquires body operation information for a subject who is traveling upon a treadmill, and applies the acquired properties to a given computational formula to compute the subject's running form score. The computational formula is generated on the basis of a correlation between the characteristics of a plurality of runners and an overall evaluation which an expert applies to the travel by the plurality of test runners.