A bearing for a wind turbine may generally include an outer race, an inner race and a plurality of roller elements positioned radially between the inner and outer races, with the roller elements including a first roller element and a second roller element. The bearing may also include a sensor assembly having a load sensor positioned between the first and second roller elements. When the sensor assembly is compressed between the first and second roller elements during operation of the wind turbine, the load sensor is configured to detect a compressive load transferred through the sensor assembly.