To provide a resin composition for multilayer forming, having excellent rigidity, dimensional stability to temperature change, impact resistance and heat distortion resistance, giving good adhesivity to a weatherability composition (AES; ethylene-α-olefin copolymer or ethylene-α-olefin-polyene copolymer) without using an adhesive and giving a formed article having good surface appearance, suppressed deformation caused by thermal shrinkage and high impact resistance and provide a multilayer formed article produced by using the composition as the substrate and coating the substrate with a weatherability composition (AES).

The resin composition for multilayer forming is composed of 85-95 wt.% thermoplastic resin (A) composed of a graft polymer produced by the graft polymerization of an aromatic vinyl monomer, methyl methacrylate and an alkyl (meth)acrylate except for methyl methacrylate to a rubbery elastomer or a mixture of the graft polymer and a copolymer composed mainly of the above monomers and 5-15 wt.% glass fiber (or 4.5-14.5 wt.% glass fiber and 0.5-10 wt.% finely crushed glass having an average particle diameter of 1-20 μm). The multilayer formed article is produced by using the resin composition as a substrate and coating the substrate with a weatherability composition (AES).