A fluid handling device for liquid hydrogen, in which piping sections that circulate liquid hydrogen are constituted from an inboard arm , an outboard arm , and elbow piping , and the various piping sections are rotatably connected by a swivel joint section , the fluid handling device for liquid hydrogen whereby the piping sections are formed having a vacuum-dual-pipe heat insulation structure, the swivel joint section is constituted by connecting, to enable relative rotation, an outer ring section that is connected with one of the piping sections to be connected and an inner ring section that is connected with another of the piping sections, with a bearing section interposed, helium gas is sealed into a boundary relative-rotation section between the outer ring section and the inner ring section in which the bearing section is interposed, and a state is induced in which the pressure within said boundary relative-rotation section is higher than atmospheric pressure; and between an outside-air-contacting wall section that is exposed to the atmosphere and in contact with outside air and a liquid-hydrogen-contacting wall section that is in contact with the liquid hydrogen being circulated there is provided a heat-conducting path extension section that extends in the axial direction of a vacuum section and that is provided with one end connected with the outside-air-contacting wall section and the other end connected with the liquid-hydrogen-contacting wall section, the heat conduction distance between the outside-air-contacting wall section and the liquid-hydrogen-contacting wall section is extended, the outer ring section is provided with a straight-pipe-shape fitted part with a vacuum dual-pipe structure connected with an outer-ring-relative-rotation section provided with the bearing section, the inner ring section is provided with a straight-pipe-shape fitting part with a vacuum dual-pipe structure connected with an inner-ring-relative-rotation section that engages with the outer-ring-relative-rotation section, the straight-pipe-shape fitting part is fitted with and engages the straight-pipe-shape fitted part to connect the outer ring section and the inner ring section, through the fitting and engagement of the straight-pipe-shape fitting part and the straight-pipe-shape fitted part, the vacuum sections are formed in two layers between an outside pipe section of the straight-pipe-shape fitted part that will become the outside-air-contacting wall section and an inside pipe section of the straight-pipe-shape fitting part that will become the liquid-hydrogen-contacting wall section, a pipe wall overlap section is formed in which an inside pipe section of the straight-pipe-shape fitted part and an outside pipe section of the straight-pipe-shape fitting part overlap in a manner allowing relative rotation, and the pipe wall overlap section becomes the heat-conducting path extension section and extends the heat conduction distance between the outside pipe section of the straight-pipe fitted part that will become the outside-air-contacting wall section and the inside pipe section of the straight-pipe-shape fitting part that will become the liquid-hydrogen-contacting wall section, and the heat conductivity between the outside pipe section of the straight-pipe-shape fitted part and the inside pipe section of the fitting section straight-pipe-shape fitting part is reduced; the inside pipe section and the outside pipe section of the straight-pipe-shape fitting part are mirror-finished; a stacked-layer vacuum heat insulation section in which radiation shield sheets and spacers are stacked is provided between said inside pipe section and the outside pipe section, heat conduction due to radiation between the outside air-contacting wall section and the liquid hydrogen-contacting wall section is reduced; and the heat conductivity between the outside-air-contacting wall section and the liquid-hydrogen-contacting wall section is reduced. <EOS>