Signals of Low speed, high-loaded bearings in incomplete rotating state have some characteristics, such as nonstationary, varying load, multi vibration resources and no character frequency. Traditional frequency analytical method can’t solve the problem of fault diagnosis of this kind of bearings. Start with angle domain, a new fault diagnosis method based on characteristics of angle domain is put forward in this paper. And the new feature characteristics, touching frequency and parts contacting angle, are extracted from the vibration signals and rotation signals. This method is applied to diagnose the fault of Low speed, high-loaded bearings in incomplete rotating state. The diagnosis result proves this method is feasible and valid.