To provide a plastic pipe which can be made lighter in weight because of the smallness of gas permeability regardless of the smallness of thickness.

In a multilayer pipe (1) obtained by molding a plastic lamination sheet (2) having a gas barrier property in the shape of a pipe, the plastic lamination sheet includes a gas barrier layer (4) obtained by laminating on at least one surface of a plastic base material (5), as a first layer, an evaporation thin film layer (6) made from metal, metal oxide or a mixture of them, and, as a second layer, a coating layer (7) obtained by applying a coating agent with water-soluble polymer, and a water solution containing at least one between (a) one kind or more of alkoxide and/or a hydrolysate of the alkoxide or (b) tin chloride, or a water/alcohol mixture solution as a main agent, and heating and drying.