The calibration characteristics of chamfering total pressure probes were studied by numerical simulation in the supersonic condition,and the key impacts of the calibration characteristics were analyzed.The total pressurecoefficient changes with position,pressure,temperature and Mach number.The numerical simulation results were compared with the experimental results.The results show that selecting the installation location has great influence on the total pressure of the chamfer total pressure probe.The absolute value of the pressure coefficient is smaller when the probe is placed nearer to the upstream of the tunnel.The absolute value of the total pressure coefficient of the chamfering total pressure probe decreases with the increasing of temperature and pressure,and increases with the increasing of a number.