Abstract: Terahertz (THz) wave has aroused extensive attention since the highly penetrability and wide band signal. And it has been identified that the high resolution range profiles (HRRP) possess great potentials in target detection, recognition, imaging, and so on. However, the properties of target HRRP in THz band are rarely investigated. This paper researched the targetaspect sensitivity with the deterministic model, and planning to overcome it by extracting the average HRRP based on the principle eigenvector of covariance matrix. Then, according to the different distribution of scattering center, the range cells were classified. Rayleigh, Ricean and Mixture models were proposed to describe the statistical characteristics of range cells amplitude histogram. The Method of LogCumulants (MoLC) and Dictionarybased Stochastic ExpectationMaximization (DSEM) methods were utilized to estimate the parameters of statistical models. Finally, the experiments of target HRRP properties in THz band were performed with the THz high resolution radar system. The experimental results showed that average HRRP of multiple HRRPs has higher correlation coefficients with other HRRPs than single HRRP does. And the statistical characteristics of the range cell can be described by the mixture model precisely.