In Lower Silesia, three goldenrod species introduced from North America are found: Solidago gigantea Aiton (late goldenrod), S. canadensis L. (Canadian goldenrod) and S. graminifolia (L.) Elliott. (grass-leaved goldenrod). A native species is also found: Solidago virgaurea L. (common goldenrod). Distribution of these species was surveyed using sampling plots in a 10x10 km grid. The impact of increasing cover of goldenrods on biodiversity of patches of invaded vegetation was assessed. Biodiversity was described by the number of co-occurring vascular plant species inside 100 m2 plots placed in vegetation patches with goldenrods. The Shannon-Wiener diversity index was also calculated. The habitat preferences of particular Solidago species were examined. The most numerous goldenrod species in Lower Silesia were Solidago canadensis and S. gigantea, which were found in a similar number of plots. Distribution of thes two species were clumped in spatial scale of the whole study area. Solidago canadensis and S. gigantea do not differ with respect to their habitat preferences. The number of plant species as well as the Shannon-Wiener diversity index significantly decreased with increasing cover of S. canadensis and S. gigantea.