Abstract: The flora and vegetative food resources on Neilingding Island were investigated , and the proportion of edible parts of about 200 species was determined. The results show : (1) There are about 200 species as food resources for Macaca mulatta in the Island , and the edible pares are mainly leaves and fruits ; (2) the M. mulatta’s habitats are mainly the broad2leaved forests and bushlands ; (3) the plant species as its food resources are mainly tropical or tropical-subtropical elements , which is the characteristic and (4) it is estimated that the maximum number of M. mulatta population is 820～1640 (mean 1230) of the vegetation and the optimal number is about 743～1485 (mean 1114) . The population in this number consumes about 10 %～ 20 % of the of high quality food resources.