Novel semiconductor-base nanotechnology is gradually moving into new applications in the world economy. Semiconductor application requires increasing of investigations in the direction of their properties. The primary criterion of semiconductor suitability for use in semiconductor devices is its electrical properties, particularly current carriers mobility. Therefore, the problem connected with the explanation of the experimental results of current carriers mobility on the base of theoretical formulas is very urgent. In the present paper current carriers mobility due to ionized impurity scattering is discussed and calculated using numerical methods. Calculations have been done for different temperatures and different range of current carriers concentration in InAs.