Calculations of the electron mobility of n-type InSb have been performed at different temperature regimes using relaxation time approximation method. The temperatures were classified into three main categories according to the electron mobility behavior. A high temperature range was considered from room temperature down to approximately 100 K. Intermediate temperature range was taken from 100 K down to 50 K. The low range was assumed from 50 K down to 10 K. In these temperature ranges a number of scattering sources have been discussed. Neutral impurity scattering, ionized impurity scattering and lattice scattering were analyzed. At high temperature regime, the intrinsic behavior of n-doped InSb was noticed. At intermediate temperature range...