Subject. This article explores the basic elements of the engineering infrastructure of smart cities. Objectives. The article aims to systematize theoretical descriptions of the engineering infrastructure of a smart city. Methods. For the study, we used a logical analysis and systematization. Results. The article highlights the main areas of infrastructure development of smart cities. Conclusions. Improving process management mechanisms, optimizing urban infrastructure, increasing the use of digital technologies, and developing socio-economic innovation improve the quality of the urban environment in a digitalized environment. And improving the efficiency of urban planning and security, studying its properties and characteristics, and forming an effective urban information system lead to its functional transformations.