Growing density of wild boar(Sus scrofa) led to human-wild boar conflict in Fenghuang Mountains National Nature Reserve.Aiming at determining density of wild boar and estimating the nutritional carrying capacity,on one hand we performed a study to analyze forage components of wild boar by line transect backward snow track survey,former records and observe method to identified food habit in field survey during late winter to early spring of 2009 and 2010 in the reserve;and on the other hand,available plants biomass was analyzed. We located 30 line transects,(total length 134km) each width for 100 meters,length for 3—5km.On each line transect,we designed large sample plots(10m*10m) at 200m intervals,and each large sample plot was partitioned into five small sample plots(1m×1m).When tracing backward the snow tracks,we identified as one individual,while,what if we met several tracks left on the same transect between 30m,we followed until they parted away and the number was clear enough for counting.Nutritional carrying capacity of wild boar was determined and calculated by total energy from integrating data of crude protein,fiber and crude fat.Per gram crude protein and fiber euqals to 16.74kJ and crude fat 37.66kJ respectively.The daily energy requirement of each wild boar was based on the research of the domestic pig.Also the data of fecals,beding sites,feeding sites of wild boar were collected as ancillary factors to get more precise results. Results showed that wild boars fed mainly on Equisetum hiemale,Pinus koraiensis,Juglans mandshurica,Quecusmongolica,Padus racemosa,Corylus heterophlla,Carex spp.and Aralia elata.The nature reserve could provide 7.375 ×107MJ energy for wild boar population and the energy requirement of every wild boar was(14 677.698±409.92) MJ in winter.According to energy from habitat and that required by wild boar,we figured out that the winter nutritional carrying capacity and optimum population density of wild boar should be 1 006±28 individuals and(3.79±0.11) ind/km2 respectively.However,we found more than 30 iron knots made for trapping wild boar and 2 individuals were poached by local people during the field survey.Therefore,we added 20% risk coefficient to got a more precision result,considering the death of wild boar from human disturbance(such as poaching and trapping).In this condition,the optimum population of wild boar should be at about(603±17) individuals and the optimum population density was(2.27±0.06) individuals/km2.Finally we found out the actual population size of wild boar was 596±155((2.24±0.58) ind/km2),and habitat carrying capacity was around actual population size of wild boar.We suggested that the wild boar couldn′t be hunted and managers should take actions to prevent habitat degeneration by wild boar overabundance.