Aerodynamic performances of three Busemanntypes of silent supersonic biplanes were studied by a low-speed wind tunnel experiment. These wings have the plane configurations of the front-side tapered, the rear-side tapered and the both-side tapered shape. Lift, drag and pitching moment of the biplanes were measured in the both cases of their pitching motion and the static conditions by using the compact force balance developed in the authors' laboratory of Tottori University. All of the three biplanes show the same CL characteristic as a thin wing at a low angle of attack. The biplane with the front-side tapered shape has the larger lift inclination in the attack angle from eight to seventeen degrees than the other biplanes and indicates clearly the stall phenomena at the attack angle of seventeen degrees. It was found that the front-side tapered wing generates leading edge separation vortices just like a delta wing and the occurrence of the vortex breakdown is the reason for the stall. The dynamic characteristics of lift, drag, and pitching moment in their pitching motions drew hysteresis loops around the static results with an angle of attack. The aerodynamic performances with the low frequency pitching of 0.5 Hz approaches closer to the static ones than the results of the high pitching, 1.0 Hz. It is based on the fact that the airflow around the biplane cannot follow immediately the motion of the biplane. Furthermore, the longitudinal static stability of the three biplanes became worse in the higher pitching motion.