To provide a method of manufacturing easily and simply a multi-layered product excellent in interlayer adhesion force and cold shock property, laminated by polyamide and fluorine-containing ethylenic polymer, by a simultaneous multi-layer coextruding method, without requiring any additional process and without any specific limited adhesive material.

The manufacturing method of the multi-layered product comprises a step of laminating at least polyamide (A) and fluorine-containing ethylenic polymer (B) by the simultaneous multi-layer coextruding method employing a coextruding apparatus consisting of a die and a plurality of extruders supplying a resin to the die to yield a laminate composed of the (A) and (B), a temperature of the die being in the range of 260°C to 310°C.