Niche characteristics o f 25 dominant populations in the forest communities o fBa baoshan,Guangdong,were studied by computing their niche breadth value andniche overiap value.The result showed that,among the dominant populations,Castano psisfargesii,C.cariesii,Lithocamus hancei and Schima superba had the highestniche breadth value,and the descending order of niche breadth was to some extent inaccordanee with the IV(Importance Value)sequence of the po pulations.Niche o verla pwas closely related to niche breadth Two populations with wide niche breadths usual-ly had a higher niche overlap value than those with narrow niche breadths o r whenone population had wide niche breadth and the other narrow niche breadth.Finally,the paper gives brief remarks on the niche studies and its application to forestrymanagement and silviculture.