The study uses data from 2288 sample plots established in forest stands with limited human interference in the Carpathian National Parks (the Bieszczady, Magura, Gorce, and Babia Góra National Parks). The research area is characterised by a full habitat spectrum of lower montane zone forest stands of the western arc of the Carpathians. The aim of the study was to verify the hypothesis that among trees forming a stand, species that have a positive or negative impact on the number of natural young seedlings of firs, beeches, spruces and sycamores can be separated. A positive impact of basal area of potential seed trees of a given species on the number of the species’ regeneration was found. A significantly greater impact of basal area of seed trees on the number of renewals of a given species was observed in the case of spruce and sycamore than in the case of shade-tolerant species as fir and beech. However, the increase in basal area of all trees of a given species (with the diameter at breast height, or DBH, from 7 cm upwards), limited the number of natural young seedlings of this species. The impact of species growing in the stand on the number of natural young seedlings depended on the scale (11, 5.3 meters) in which the phenomenon was observed. The increase in the basal area of pioneer species in the stand limited the number of natural young seedlings of firs, beeches and spruces, while favouring of sycamores. More numerous regeneration of spruce was observed in the immediate vicinity of sycamore (3-metre scale), but on the 11- and 5-metre scale the occurrence of sycamores acted the opposite. Spruce growing in the stand had a positive impact on the number of natural young seedling of all analysed species (especially on a 5-metre scale), in contrast to fir which showed no clear positive relationship on any scale with the natural young seedlings, of its own or other species. The presence of beech in the stand favoured the renewal of fir and spruce, beech had this kind of impact for natural young seedlings of spruce. The occurrence in a stand of tree species that positively impact the development of natural young seedlings of a given tree species does not guarantee their renewal. However, if favourable conditions for renewal occur, then in places of occurrence of species positively impacting the renewal of a given species will be more numerous.