Polypores are important components of forest biodiversity; most of them are wood-decaying fungi and are critical for the decomposition of coarse woody materials, playing key roles in nutrient cycling and energy flows. The poroid wood-inhabiting fungi of the Great Xingan Mountains, China, have been little studied. Difficulties include species identification and lack of relevant information. Our analyses of polypore diversity and population structure in the Great Xingan Mountains are based on 10 years of field investigation and laboratory analyses. Species diversity in this area is rather high, accounting for 21.36 % of all Chinese polypore species, and including 129 species belonging to five orders, 11 families and 56 genera of Basidiomycota. The dominant family is the Polyporaceae, including 21 genera and 58 species, and another major family is the Fomitopsidaceae, which including 11 genera and 24 species. The majority of polypores in the Great Xingan Mountains are in these two families. The dominant genera are Postia, Polyporus, Trametes and Phellinus, and nine, nine, eight and seven species were respectively found in these genera. Biogeographically, these polypores can be divided into three groups at family level: cosmopolitan (Hydnodontaceae, Hymenochaetaceae, Meripilaceae, Meruliaceae, Phanerochaetaceae, Polyporaceae and Schizoporaceae), north temperate (Albatrellaceae, Fomitopsidaceae and Gloeophyllaceae), pantropical (Ganodermataceae); three groups at genus level: cosmopolitan (33 genera), north temperate (21 genera), pantropical (2 genera); seven groups at species level: north temperate (52.71 %), cosmopolitan (34.88 %), Asian-European (4.65 %), East Asian (3.1 %), East Asian-North American (2.33 %), pantropical (1.55 %), and endemic (0.78 %). The dominant element is clearly north temperate but with a strong cosmopolitan influence. According to the occurring frequency in the studied forest, these polypores can be divided into four groups: common species (65), occasional species (34), rare species (24) and threatened species (6), and the common species are dominant. Ecologically these polypores can be divided into three types: saprophytic (99 species), parasitic (27 species), and symbiotic (3 species); saprophytes are clearly dominant. Among the 126 wood-rotting species, 93 species cause white rot, and 33 species cause brown rot. The percentage of brown rot fungi was found to be significantly higher in Great Xingan Mountains than in other part of China. The main trees in the Great Xingan Mountains are in genera of Betula, Larix, Populus and Quercus. Population structure was compared on the main angiosperms and gymnosperms, 60 species were found on Larix, among these polypores, and 30 of them cause brown rot and the other 30 species cause white rot; 46 species grow on Betula, and 8 species cause brown rot and 38 species cause white rot; 24 species occur on Populus, and 2 species cause brown rot, while 22 species cause white rot; 19 species live on Quercus, among them 3 species cause brown rot and 16 species cause white rot. White rot fungi were mostly found on angiosperm wood, while white and brown rot fungi were found with equal frequency on gymnosperm wood. It seems that the brown rot polypores are very important for the regeneration of larch forest. Most polypores grow on fallen trunks or rotten woods in natural forest, the species diversity of polypores in forest plantation is very low, according to the ecological habits of polypores, the reserve of fallen trunks or rotten woods in forest is very important to preserve the polypores.