The parameters of the site index curve model were solved by using particle swarm optimization(PSO) algorithm,with the minimum error in estimation of dominant height and site index as the target function.An application example is introduced to test the proposed method,and the estimation result is compared between PSO and immune algorithm.Comparison result shows that the parameters solved by PSO can decrease the overall error,increase the precision,improve the fitting effect of the site index curve model,thus increase the estimation precision of young forest.This research is hoped to provide new idea for parameter solving of grow model in forest management and related research,and expand the application of PSO in forestry science as well.