The thesis deals with invasive plant species. The aim of the thesis is to map these plants in the selected protected area on the territory of Slovakia. The first part contains the general characteristics and description of the invasive plants, the consequences of their spread and the methods of disposal of these plants. In addition, specific types of invasive plants occurring in the selected protected area of Polana, namely Hrochotska dolina, are described. The second part is characterized by this protected area, described work methodology and evaluated data obtained from the survey. Our species of invasive plants in the selected area were observed: Solidago canadensis L., Stenacti sannua (L.) Nees., Aster lanceolatus Willd. and Helianthus tuberosus L. The smallest population was the species of Helianthus tuberosus L., which was deliberately planted as a decorative plant. Other species had self-sustaining growth.