The paper aims to point out the importance of the sustainable development of tourism in Serbia. To overcome the shortcomings of sustainable tourism development, the authors present the tourist attractions and advantages of Serbia and the city of Belgrade, the central region, which could have a positive impact on the influx of tourists and the image of the tourist destination. The subject of the work is the consideration of environmental protection, mitigation of negative environmental impacts on tourism, which plays an important role in sustainable ecological development. The authors applied an appropriate methodological analysis of the city of Belgrade, which belongs to the most developed tourist region of the country. PEST(E) analysis describes the political, legal, socio-cultural, economic, technological, and ecological elements of the city of Belgrade to identify factors that influence sustainable development and environmental awareness. The paper also used a survey, in which respondents' answers were processed using the statistical method of the X 2 test. Investing in sustainable tourism means investments at the regional and local level in ecological infrastructure, investments for the formation of an ecological geographic information system, and promotional management activities to improve the rating of the competitive advantage of the sustainable tourist development of the cities of Belgrade and Serbia.