In Poland, mountain national parks are visited by about 8 million tourists annually. As a result, national parks must have a properly developed infrastructure to accommodate such a large number of people. Tourism development in mountain national parks satisfies the needs of tourist participants and should increase the attractiveness of the area, fit into the cultural concepts of a given region, and promote its development. The research aims to determine the consequences of making mountain national parks available in Poland and determine the factors determining the attractiveness of the protected area and the related tourist burden. Nine mountain national parks located in Poland were selected for the research. An interview was conducted with employees of mountain national parks concerning (a) the tourist burden on the national park, (b) the tourist management of the national park and its surroundings, and (c) the impact of tourist traffic on the natural environment. Parameters characterizing the intensity and spatial character of tourist traffic, tourist management, and the influence of tourist traffic on the natural environment of mountain national parks are discussed. The study presents the parameters determining: tourist traffic density, tourist route density, and tourist traffic intensity. A map of the development of the surroundings of national parks was presented, and its influence on tourist traffic was determined. The obtained results were discussed in the context of the consequences of tourist traffic in mountain national parks. The result of the work was the development of a map of the tourist load of mountain national parks in Poland. Tourism is of crucial importance for the proper functioning of national parks. However, if not properly cultivated, it threatens the fauna and flora of such areas. Rational use of natural resources by tourists visiting mountain national parks is crucial to maintain the balance between man and nature. Proper supervision and management in the national park, as well as the collective responsibility of tourists visiting national parks and the community living in their vicinity, is of fundamental importance for the proper functioning of the system in national parks and nearby tourist destinations.