The tutorial provides general information on the design features of underwater marine equipment, principles for calculating the strength of structures of submarines and underwater vehicles. External loads, criteria and methods for checking the strength of structures are considered. The materials presented in the training manual can be useful to bachelors, specialists and masters of shipbuilding and engineering specialties, as well as engineers involved in the design design of underwater marine equipment. In addition, the manual can be used when studying the device of underwater equipment and when developing the technology of manufacturing the body of the structure, taking into account the effect on strength.