<p>Provided is a wheel bearing with a sensor capable of calculating continuous estimated load values according to various input load conditions while reducing the load estimation error by correcting non-linear characteristics of the sensor, and capable of outputting estimated load values with the smallest possible detection time delay. Sensor units (20A, 20B) are provided to the fixed member among an outer member (1) and an inner member (2) of a wheel bearing. The sensor unit includes: a distortion generating member (21) having three or more contact/fixing portions which are brought into contact with and affixed to the fixed member; and two or more sensors (22A, 22B) attached to the distortion generating member (21) to detect distortion. The wheel bearing with a sensor further includes: a first load estimating means (31) for calculating the load acting on the wheel bearing on the basis of the average value of the sensor output signals; a second load estimating means (32) for calculating the load on the basis of the average value and the amplitude values of the sensor output signals; and an estimated load output means (33) for outputting an estimated load value by combining the calculation results of these load estimating means (32) at a ratio corresponding to the wheel rotation speed.</p>
