Tanks are every army's striking force. Therefore, fire power, armor protection and mobility are the main parameters of tank valuation. In order to achieve good mobility, an appropriate propulsion system is required. The first part of the paper presents the direction of the development of the propulsion system of modern tanks, and the aspects of the selection are explained. The main part of the work analyzes in detail the modern Diesel engines and gas turbines. In parallel, specific forces are shown through stages of development and different performances. It is about supercharging, "Common rail" and hyperbar Diesel engines. Hence, an analysis of their constructional design and improvements is provided. Also, an overview of the development of gas turbines in the United States and Russia is provided, as is an analysis of their performance, consumption and maintenance. And lastly, the final part of the work discusses the installation aspects to be followed when selecting a propulsion system. It analyzes the time it takes to replace the drive system and the required volume of installation along with all the necessary propulsion engine systems.