Lightweight fiber-reinforced thermoplastic resin molding

The present invention provides a lightweight fiber-reinforced thermoplastic resin molding comprising a thermoplastic resin and having a skin layer and a beam-supported structure layer, the thermoplastic resin containing reinforcing fibers whose average fiber length is maintained at 1 mm or more, the skin layer having almost no voids, the beam-supported structure layer containing reinforcing fibers which are intertwined complicatedly with each other and are fixed to each other with the thermoplastic resin in the vicinity of their contacts, wherein the beams forming the beam-supported structure layer are arcuate as an aggregate in the plane direction of the molding, said a lightweight fiber-reinforced thermoplastic resin molding having a high percentage of void and is lightweight and excellent in bending rigidity.