The invention belongs to the technical field of titanium dioxide performance testing, and discloses a method for rapidly testing weather resistance of titanium dioxide and application. The method comprises the following steps of (1) uniformly mixing materials for preparing a test sample wafer, wherein the material formula comprises the following components in parts by weight: 100 parts of polyvinyl chloride resins, 5-10 parts of titanium dioxide, 3-10 parts of lead salt stabilizers, 2-8 parts of chlorinated polyethylene, 1-3 parts of plasticizers, 3-20 parts of calcium carbonate, 1-3 parts of ACR-401 and 0.1-1 part of paraffin; (2) processing a mixture obtained in the step (1) into a sample wafer by adopting an extruder; (3) cutting the mixture obtained in the step (2) into a test sample wafer, and testing color values L0, a0 and b0; (4) sealing the test sample wafer in water, isolating air and carrying out sun exposure for 2-48 hours, and testing color values L1, a1 and b1; and (5) computing a color difference before and after the sun exposure, and judging the weather resistance of the titanium dioxide. According to the method, the weather resistance of the titanium dioxide can be rapidly, efficiently and accurately detected.