A thermoplastic resin composition, a molded body, and first and second production methods are disclosed. The thermoplastic resin composition contains a polyolefin resin, a polyamide resin, and a modified elastomer and shows non-Newtonian properties in a fluidized state. The molded body includes the thermoplastic resin composition. The first production method includes molding the thermoplastic resin composition at a shear rate of 80 sec−1 or more and a standby step in which resin composition is on standby at a shear rate of 0 sec−1 or more but less than 80 sec−1. The second production method includes molding the resin composition at a shear rate X1 to obtain part of a molded body and molding the resin composition at a shear rate X2 to obtain another part of the molded body, wherein an absolute value of a difference between X1 and X2 is 200 sec−1 or more.