This paper emphasizes on the application of projection image method in vertical wind tunnel, and the test methods, testing e-quipment, image collection and processing method of Parachute-Bomb stable sweeping tests, and the study on the steady state characteris-tics of parachute-bomb. The result of the investigation indicates that the system of experimentation can work properly. The parameters such as the missile body attitude, the scanning angle of parachut-bomb system and the measurement results of the average rotating speed of pro-jectile which were tested by measurement system were consistent with the results of outfield.