This study investigated the montane vegetation in upper valley of Peishihshi, north-east Taiwan. A total of 560 plants and 6 environmental factors in 33 stands were analyzed by detrended correspondence analysis (DCA) and two-way indicator species analysis (TWINSPAN). The analyses recognized 6 main vegetation types as follows: A. Ficus fistulosa - Machilus japonica var. kusanoi Type B. Litsea acuminata – Machilus japonica var. kusanoi Type C. Castanopsis uraiana – Castanopsis carlesii var. sessilis Type D. Gardenia jasminoides – Castanopsis carlesii var. sessilis Type E. Quercus longinux – Machilus thunbergii Type F. Euscaphis japonica – Quercus sessilifolia Type The above types have been checked against the vegetation classification system and assigned to the former reported associations. This study discovered 1 new vegetation types in the studied area.