The invention discloses a test method of measuring leakage amount of labyrinth seal structure. The test method of measuring leakage amount of labyrinth seal structure includes the following steps: 1)processing a test piece; 2) processing a gas collection cavity; 3) before the test, measuring the atmospheric temperature and pressure at the testing moment; 4) performing a test of measuring seal leakage amount, recording a curve that pressure changes following time change, in the seal cavity, and stopping the test after the pressure in the seal cavity rises to 95% of the entrance pressure; and 5) according to the test result, drawing a function curve that the seal leakage amount changes following different differential pressure. The test method of measuring leakage amount of labyrinth seal structure is simple, is low in the cost and is wide in the result application fields. The test method of measuring leakage amount of labyrinth seal structure solves the problems that a traditional sealleakage amount test method is less in the differential pressure points and is not continuous in the test results, and the measuring range is metered across the flow when the test flow changes from large to small so that the flow test is not accurate.