A vegetational analysis was made in the southern parts of the Muronouchi crater of Mt.Sambe. The vegetation of Fagus crenata, Fagus japonica and Acer carpinifolium was newly found on this investigation. This vegetated area is characterized by lies near the fumalore so called "Tori−zigoku"，and also by little superficial deposits and much boulder gravel deposits. The vegetational pattern of（Quercus crispula-----Sasa Veichii var, hirsuta）was observed on the slanting areas covered with superficial deposits. Other vegetational patterns were observed at the same slanting areas covered with boulder gravel deposits. These are the patterns of（Fogus crenata-----Carex Morrowii），(Fagus japonica ----- Carex Morrowii),（Carpinus carpinoides ------ Carex Morrowii) and (Acer pictum ----- Carex Morrowii). At the bottom of the crater，different vegetations were seen. These are vegetational patterns of （Quercus dentata ----- plants of Graminae）and（Pinus Thunbergii ----- plants of Graminae）at the upper part of the bottom. At thelower part of the bottom，vegetations of tree or shrub layers were not seen but only a herb layer These may have been caused by acidif ied soil from fumaroles in this area.