An ethylene-vinyl alcohol copolymer resin composition containing an ethylene-vinyl alcohol copolymer and a metal compound, and having a peak at 2θ=2 to 15° when measured by wide-angle X-ray diffraction using CuKα ray, as an ethylene-vinyl alcohol copolymer resin composition having an excellent gas barrier property in a high humidity environment, particularly an excellent oxygen barrier property in a high humidity environment.