The invention discloses a weight-based combined test case set prioritization sorting method and system, and the method comprises the following steps: 1, determining the range of combined coverage force t according to a parameter set of a to-be-tested program, generating a t-dimensional combination of the to-be-tested program based on the combined coverage force t, and defining the t-dimensional combination as a set A; 2, prioritizing the test case sets of the programs to be tested, recording the time cost of optimizing the whole test case set each time and the average time cost after 200 timesof operation, and outputting the result set and the time cost in the form of files; And step 3, performing a simulation experiment on the obtained optimized test case set to the program to be tested,and recording the error detection rate of the program to be tested. According to the method, on the premise of ensuring the time cost, the obtained optimized test case set can have a better error detection rate in a simulation experiment, so that the time cost required by a test stage in an actual test is reduced, and the test efficiency is improved.