The invention discloses a high-hardness polyurethane elastomer pressure-bearing support material for bridge and a preparation method and a using method thereof. The high-hardness polyurethane elastomer pressure-bearing support material is prepared from a component A and a component B. The component A is prepared from, by mass, 100 parts of polyhydric alcohols, 10-20 parts of small molecular alcohols and 60-140 parts of mixed isocyanate. The component B is a chain extender. The mass ratio of the component A to the component B is 100/24-32. The polyhydric alcohols are PTMG or PPG, and the number-average molecular weight is 500-3000. The mixed isocyanate is the mixture of two of MDI, PPDI, T-100, T-80, HMDI, IPDI and HDI. The small molecular alcohols are the mixture of one or two of EG, BDO, DEG, PG, DPG and the like. The material is long in pot life and good in operative weldability, and the hardness is 80+/-2D; the solidified polyurethane elastomer material is used as the pressure-bearing support, so that the bearing capacity is improved, the using number of supports can be reduced, the replacement frequency of the bridge support is lowered, and the safety coefficient of a whole retractor device is improved.