The aim of the bachelor thesis was to determine the floristic composition of vascular plants and bryophytes, to document the identified forest communities by phytocenological records and to analyze the functional and ecological traits of recorded species in a selected area within the Šimonka National Nature Reserve in the Slanské vrchy Mts. Two representative phytocenological records were made by subjective random selection using the method of the Zürich-Montpellier school. To analyze the functional and ecological traits of the recorded species, data on life forms, life span, leaf duration, life strategies, affiliation to vegetation type and altitudinal zones, link to the forest environment, ecological specialization index, hemeroby, substrate preference and demands for light, temperature, continentality, moisture, soil reaction and nutrients were obtained. A total of 76 taxa of vascular plants and 35 taxa of bryophytes were recorded in the studied area. According to the syntaxonomic classification, the records made were classified to the association Cicerbito alpinae-Fagetum sylvaticae and Athyrio distentifolii-Fagetum sylvaticae and in terms of groups of forest types to the Fageto-Aceretum 5th/6th altitudinal zone of the B/C trophic-edaphic rank and the Fagetum humile 5th/6th altitudinal zone of the A/B rank. Based on the overall species composition, the area of interest can be classified as low beech maple woodland (Fageto-Aceretum humile higher zone). According to the diagnostic affiliation to the syntaxonomic units, most recorded species of vascular plants and bryophytes within the whole studied area belong to the class Querco-Fagetea, the order Fagetalia sylvaticea and the association Fagion sylvaticae. In the studied area, perennial and generalist species predominated but specialists were also relatively abundant, which indicates a more stable and natural habitat, however, only a third of vascular plant species and less than a half of bryophytes are characteristic of closed forests. Indicative values for light showed a slight predominance of semi-light-loving species of vascular plants and, on the other hand, a prevalence of semi-shade-loving species of bryophytes; similar situation was in terms of indicative values for temperature, where vascular plants had medium demands, while bryophytes indicated cold or very cold conditions. The values for continentality indicate a predominance of oceanic to suboceanic species of vascular plants, while most species of bryophytes are intermediate and subcontinental. Similarly, in terms of vascular plant demands for soil reaction and nutrients, taxa of mildly acidic to neutral and moderately rich to rich soils predominated, while bryophytes showed a higher proportion of species typical for more acidic and poorer soils. Depending on the soil moisture, taxa of freshly moist to moist soils predominated in both groups. The high preferences of the recorded bryophytes for all main types of substrate (rocks, bark of live trees, dead wood and soil) indicate a more preserved and primeval forest-like character of the environment with a diversity of available micro-habitats. The presented bachelor thesis contributes to the knowledge of the flora of vascular plants and bryophytes of the Šimonka National Nature Reserve as well as the Slanské vrchy Mts. The contribution of the thesis is also a more detailed evaluation of environmental conditions using functional and ecological traits of species of different groups of plants and based on their comparison according to data from different sources adapted for different regions of Europe.