There are few papers about terahertz wave propagating in magnetized plasma. Adding constant magnetic field around space crafts and choosing terahertz wave as communication signal are two effective ways to solve the famous blackout problem. It is necessary to study the properties of terahertz wave propagation in magnetized plasma sheath. This paper has established the one-dimensional model to describe electromagnetic wave passing through the magnetized plasma sheath. A numerical analysis method is adopted to calculate the reflection coefficient, transmission coefficient and attenuation coefficient of the terahertz wave propagating in magnetized plasma sheath. The variations of the terahertz wave propagation properties with the terahertz wave frequency, plasma density, plasma collision frequency, the thickness of the plasma and magnetic field intensity are acquired. The simulation shows that the magnetic field effectively reduces the attenuation when the terahertz wave propagates in plasma sheath. Except the peak value of the attenuation, the value is less than 5 dB. This phenomenon shows that the communication blackout problem is solved effectively. The result can be used as reference for designing hypersonic vehicles with magnetic window antenna using terahertz wave as communication signal.