PROBLEM TO BE SOLVED: To provide a multi-layer pipe having heat insulation performance and fire resistance performance. A multilayer tube having an inner layer, a foamed layer, and an outer layer, wherein the inner layer, the foamed layer, and the outer layer each contain a thermoplastic resin, and the multilayer tube has a heat-expandable graphite. The content of the heat-expandable graphite with respect to the total amount of the inner layer is 5 to 16% by mass, the content of the heat-expandable graphite with respect to the total amount of the foamed layer is 0 to 5% by mass, and the heat-expandability with respect to the total amount of the outer layer. A multilayer tube having a graphite content of 0 to 2% by mass and a content of the thermally expandable graphite of 2 to 7% by mass based on the total amount of the multilayer tube. [Selection diagram] Fig. 1
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