The invention discloses alloy for casting a space shuttle liquid hydrogen fuel tank. The alloy is prepared from the following raw materials in parts by weight: 85-90 parts of Al, 2.0-3.0 parts of Li, 2.0-3.0 parts of Cu, 0.1-0.25 parts of Zr and 0.1-0.2 parts of Sr. The alloy has the advantages as follows: with adoption of electron beams for smelting the alloy, harmful impurity elements such as O, N, S and the like can be greatly reduced in the alloy smelting process, purity and content of Al, Ni and Cu in the alloy are increased, low temperature resistance of the alloy is guaranteed, and as the temperature decreases, strength, ductility and toughness of the alloy are greatly improved; the aluminum ingot with the grade of Al99.85 is used as a raw material, purity of Al in the alloy is further improved; an ultra-low-temperature-resistant pressure-sensitive adhesive is solvent-free, the curing temperature is low, curing time is short, the ultra-low-temperature-resistant pressure-sensitive adhesive is used for bonding flexible foam plastic and a pipe rapidly, the on-site construction process is good, the ultra-low-temperature-resistant pressure-sensitive adhesive still realizes a better adhesion effect under the condition of ultra-low temperature; and transmission of low temperature can be better insulated by the soft foam plastic layer.