The range profile is studied first in the microwave band. With the advent of the terahertz radar technology, the range profile is studied from microwave band to the terahertz band, which is the terahertz range profile (TRP). The outstanding feature of TRP is that it can obtain the 3-D shape and the range information of the target by one ultra-short pulse without scanning system. In this paper, terahertz range profile theory and simulation is investigated. Terahertz range profile simulation is studied based on the theory of beam scattering by rough target, pulse wave scattering theory and the radar equation, the calculated formula of range profile is obtained. This equation is, in part, dependent upon the target’s scattering strength which is quantified by its radar cross section. As examples, the range profile simulations are done for tilted-plate. It is indicated that the influence of pulse width, beam parameters, transmit-receive angle and target shape, roughness on the simulation results is also analyzed. This paper is offer theory bases and simulation method for abstraction and identification target feature on terahertz waveband.