A vehicle wheel supporting rolling bearing unit includes a stationary side bearing ring member, a rotation side bearing ring member, and plural rolling elements. The rotation side bearing ring member is provided with a first acceleration sensor, a second acceleration sensor, and a third acceleration sensor which are fixed on a virtual plane orthogonal to a center axis of the rotation side bearing ring member. The first acceleration sensor and the second acceleration sensor are arranged on a virtual line passing through a rotation center of the rotation side bearing ring member with a same distance from the rotation center while detection directions thereof are directed in a radial direction and are opposite to each other in the radial direction. The third acceleration sensor is arranged such that a detection direction thereof is non-parallel to the detection directions of the first acceleration sensor and the second acceleration sensor.