BirdcommunitiesweresurveyedinnaturaldeciduousforestofbothslopeareaandvalleyareaatMt.Gyebangsan(37°40'30"N,128°30'1"E),GangwonProvince,SouthKoreainwinter,spring,summerandautumnfromSeptember2000toNovember2001.Theinvestigatingresultsshowedthatthereexisteddifferencesinthebirdspeciescomposition,richness,birdspeciespersity,guildstructurebetweenslopeareaandvalleyarea,andtheverticalforeststructure,especiallycoverageofunderstory,anddiameteratbreastheight(DBH)distributionalsohadsignificantdifferencebetweenthetwostudyareas.Thedifferencesinhabitatstructurebetweentheareasareverylikelytohaveinfluencesonhowbirdsusedtheavailablehabitat.