To provide a light wheel supporting roller bearing device wherein problems such as a rigidity shortage, removal of pre-pressure, and peeling caused by riding-over of a rolling element are difficult to occur.

The wheel supporting roller bearing device 1 includes: a hub ring 2 having a first inner track surface 20a on an outer circumferential surface; an inner ring 3 having a second inner track surface 20b on an outer circumferential surface and integrally fixed to the hub ring 2; an outer ring 4 having a first outer track surface 21a and a second outer track surface 21b opposite the first inner track surface 20a and the second inner track surface 20b; and two rows of rolling elements 5 and 5 arranged to roll between the first inner track surface 20a and the first outer track surface 21a and between the second inner track surface 20b and the second outer track surface 21b. The inner diameter side member 31 of the outer ring 4 is made of carbon steel, an outer diameter side member 32 is made of a light alloy composite material including an aluminum contained light alloy and boron carbide as a reinforcing material, the ratio of the boron carbide in the light alloy composite material is equal to or higher than 19 volume% and equal to or lower than 51 volume%.