There are provided a rolling bearing fatigue state prediction device and a rolling bearing fatigue state prediction method capable of highly accurately predicting a fatigue state of a rolling bearing even when a direction of a load applied to a rolling bearing changes. A rolling bearing fatigue state prediction device includes a load measurement unit for determining a magnitude and a direction of a bearing load applied to a rolling bearing supporting a rotating body, a load applied region identification unit for identifying a region to which a load is applied in a circumferential region of the rolling bearing, and a fatigue state prediction unit for predicting a fatigue state of the rolling bearing based on the obtained magnitude of the load and the identified load applied region.