A resin molded article which is a molded article obtained by irradiating a resin molded article containing 100 to 60 parts by weight of (A) syndiotactic 1,2-polybutadiene having a crystallinity of 5% or more and 0 to 40 parts by weight of (B) another thermoplastic polymer with an electron beam, in which the 50% stress of the molded article after the electron beam irradiation (50% M:M2) is from 1.01 to 2.5 times the 50% stress before the electron beam irradiation (50% M:M1), and the molded article has steam sterilization resistance. The molded article is excellent in flexibility and hardness, excellent in steam sterilization resistance, and useful for medical applications such as an infusion tube, an infusion solution container, a catheter and the like.