Abstract: A type of miniature driver with measuring probe 204-2 designed by ourselves for measurement of thin boundary layers is described. In the design the homemade miniature stepmotor 28BF001 serves as a main body. The driver is simple in construction （see Fig. 1） and reliable in operation. It transforms the angular displacement of the motor into linear displacement. Its minimum linear velocity is 0.00625mm per unit pulse, and its working travel is 5.0mm. The driver with an outside diameter of 28mm and height of 50mm has good static characteristics （Fig. 2）. It is found that the experimental curve A, C extremely coincides with the theoretical curve B.Two types of measuring probes 204-2 are also presented in this paper. The outer height is 0.2mm and inner height 0.1mm for one probe tip, while for another they are 0.14mm and 0.07mm respectively. Both tips possess the same outer width of 1.0mm and the inner one of 0.6mm. The configurations of both probes are the same （see Fig. 3）.The driver and the probes presented above have already been used for measuring the boundary layer parameters on the second cone of a supersonic intake working in supercritical conditions （Figs 4 and 5）. The experiments were carried out in our supersonic intake tunnel with free-stream Mach numbers 1.97 and 2.10. The boundary layer profiles were shown in Fig. 6.By observing the movement of the probes during the experiments, it was proved that the driver and probes worked steadily in a supersonic flow without vibration, and the thin boundary layer profiles measured were quite correct.