Polyurea (PU) is one of the research hotspots with a growing interest in modern coating materials, with the goal of research being complex coatings and the possibility of changing their characteristics and properties during the manufacturing process. The synthesis of polyureas requires step-sized polymerization by the reaction of isocyanate monomers/prepolymers and polyamines, with each component having at least two functions. A wide range of excellent properties, such as durability and high resistance to atmospheric, chemical and biological factors, make this polymer an excellent choice for practical applications. Polyureas are a special material because they contain both a rigid part, which is due to the use of diisocyanates and the formation of hydrogen spots, and a flexible part, which is due to the chemical structure of polyamines. In this paper, the classification, microstructure and macroscopic properties of polyurea and its application in various aspects are reviewed.