Environmental problems of cities, which by the end of the 20th century became the predominant habitat of humans, are considered. Sources of impact on the natural environment of the city and measures to protect atmospheric air, surface and groundwater, soil cover, geological environment and green spaces within the city limits are described. An analysis of the environmental situation in more than 80 cities of Ukraine has been given. A distinctive feature of this publication is a comprehensive consideration and engineering approach to solving environmental problems of cities.