The invention discloses a grouting material for expressway bridge bearings, which comprises the following components in parts by weight: 400-500 parts of cement, 300-450 parts of quartz sand, 10-20 parts of fly ash, 2-4 parts of a water reducing agent, 1-1.5 parts of a coagulation accelerator, 1-4 parts of an expander, 1-3 parts of a retarder, 2-3 parts of a defoamer, 2-5 parts of a thickener, and1-1.5 parts of polypropylene reticular fibers. The invention further discloses a preparation method of the grouting material for expressway bridge bearings. The cement uses in the grouting material adopts sulphoaluminate cement and ordinary portland cement, which not only realizes the characteristics of early strength, but also avoids the problem of strength substantial decline caused by the useof the ordinary portland cement alone. The raw materials of the grouting material have a wide range of sources and low price. The preparation method is simple, and suitable for large-scale promotion,and the grouting material has good construction performance, can realize self-flow leveling, has long operation time, and has a smooth surface after being poured, and the shortcomings of traditional mortar such as irregularity, easy cracking, easy stripping and easy dusting can be overcome.