Problem. Energy efficiency of an automobile is a characteristic of rational use of engine power and consumption of energy sources. The rational use of engine power is the implementation of the maximum dynamics of an automobile at the lowest energy consumption (power). To date, the problem of estimating the efficiency of the automobile wheel propulsion unit is one of the most relevant in modern engineering. Therefore, there is an urgent need to optimize the ability to assess the energy efficiency of automobile by obtaining a mathematical model of the efficiency of the wheel propulsion unit for further rational design of automobiles according to energy efficiency criteria. Goal. The aim of the work is to increase the ability to assess the energy efficiency of the automobile by obtaining a mathematical model of the efficiency of the wheel propulsion unit. Methodology. Analytical, mathematical and research methods were used to develop a model for estimating the efficiency of the automobile wheel propulsion unit. Results. The results of the study allowed to determine that with an increase in the maximum torque on the clutch, there is an increase in the efficiency of the latter. The obtained mathematical model of the instantaneous power consumption factor for the movement of the driven wheel allows to increase the accuracy of estimating the energy efficiency of cars. The obtained analytical expression of the estimation of the instantaneous power consumption factor of the wheel propulsion unit allows to carry out rational design of automobiles on the criterion of energy efficiency in the future. Analysis of the obtained expression showed that with increasing number of drive wheels, the efficiency of the wheel propulsion unit also increases. Originality. The originality is in obtaining a mathematical model of the efficiency of the wheel propulsion unit of automobile, which will further help to select the rational parameters of the chassis and refine the calculation of energy efficiency of automobiles. Practical value. The practical value of the study is to provide practical recommendations for improving the ability to assess the energy efficiency of the automobile by obtaining a mathematical model of the efficiency factor of the wheel propulsion unit.