Abstract: A wind tunnel test which uses TSP transition detection technique is introduced. The NACA0012 model is uniformly covered with TSP developed by AVIC ARI and ICCAS, and the model is heated before wind tunnel running to increase the temperature difference between laminar flow area and turbulent flow area around the model surface. The marks are stuck to the TSP coat which will be used in the image processing, and some of them will be used as the transition start-up roughness elements. The wind tunnel test condition is Mach 0.4 and angle of attack of 0°,-1°, -2°, -3 °, -4° respectively. The test results clearly show the difference between the laminar flow area and the turbulent flow area of the model surface, and the change along with the model angle of attack. It is shown that the TSP works well, and the marks near the model leading edge cause the transition from laminar flow to turbulent one functionated as roughness elements in this test.