In this paper, ship's electric machines will be shown. The introduction will present the development of electricity in shipping to understand its present importance. Ship's installation is specific because each ship is energetically dependent on itself and, as such, it represents a stand-alone energy plant. For the supply of marine consumers, generators, which transform the mechanical energy into electrical, are used. In order for this energy to be properly distributed to the consumer, it is necessary to adapt it, by using a transformer, which receives the electric energy into its primary winding and transforms it and transmits it through the secondary winding to the consumers. In order for the ship to be functional and safe, as required by the competent authorities, electric motors are needed, which are also the largest electrical energy consumers on board. Electric motors are used to drive various elements, such as pumps, cranes, ventilation systems, winches, steering systems and control systems. In this paper, the principles of work of the machines, their structure, the ways in which they are used, their common properties and their application in practice will be presented.