The invention discloses polypropylene carbonate type polyurethane resin. The polypropylene carbonate type polyurethane resin is composed of the following components in parts by weight: 4-10 parts of polypropylene carbonate glycol, 7-14 parts of polyhydric alcohol, 0.5-3.5 parts of a chain extender with the molecular weight of less than 150, 6-14 parts of diisocyanate, 0.04-0.06 part of a terminating agent, 0-2 parts of an additive, 0.1-1 part of an antioxidant and 64-71 parts of a solvent. The invention further provides a preparation method of the resin and an application of the resin in a synthetic leather dry-method process field. With the adoption of the formula composition of the polypropylene carbonate type polyurethane resin, the polyurethane resin and synthetic leather prepared from the polyurethane resin have an excellent heat-resisting performance, but also have an excellent hydrolysis resistance effect. Furthermore, not only can the requirements on petrochemical raw materials be reduced, but also the effective utilization of carbon dioxide is also realized.