Abstract: On the basis of rationally classifying sample plots in monitoring area,a certain amount of optimum sample plots that can represent the forest resource distribution status in the monitoring area should be sampled.According to the main remote sensing and GIS factors influencing the canopy density estimation corresponding to sample plots selected,the canopy density estimating equation with sample plot as unit can be established.The optimum sample plots are the sample plots that can represent the species and distribution of forest resource in monitoring area and include the quantity and representative of sample plots.Also,how to take the optimum sample plots belongs to the question of multi_objective optimizing.In this paper,on the basis of theoretically describing mathematics model of the optimum sample plots in certain monitoring area,systematic research and analysis had been carried out through realitic instances and sampling problem of the optimum sample plots had been solved effectively.Therefore,the result can be used for guiding production practices.