To provide a tire rim assembly capable of suitably traveling on an irregular ground at a low inner pressure.

A rim 3 includes a spoke-type rim having a pair of rim base parts 4 receiving a bottom face of a bead part 2A of a tire 2, a pair of rim flanges 5 communicated with an outer tire axial end of the rim base parts 4, extending outward in a tire radial direction, and supporting the outer tire axial face of the bead part 2A, and an annular well 6 provided between a pair of the rim base parts 4, 4 and indented inward in a radial direction. An outer radial end of a spoke 11 is mounted to a mounting hole 13 provided to the well 6. This rim has a wide rim band 15 extending in a tire peripheral direction in close contact with an outer rim surface 3g from an outer end 5a of one rim flange 5 of a pair of the rim flanges to an outer end 5b of the other rim flange to cover the mounting hole 13.