Abstract: Mangrove plant of Rhizophora stylosa in the Gaoqiao National Mangrove Nature Reserve on Zhanjiang Municipality, Guangdong Province was studied. The correlations between the leaf area index(LAI) and the plant crown volume were analyzed by surveying the LAI, the plant height, the basal diameter, the crown diameter, the height of the lowest branches, then by conducting the semivariance function analyses, and testifying the LAI spatial structure of R. stylosa plants by simulating the spherical mode1. The results showed that the LAI of R. stylosa plants was spatially autocorrelated at medium level in space structure. There was significant positive correlation between LAI value and the crown volume, and the R. stylosa LAI values of the wind ward side of the tide were higher than those of the lee ward side of the tide.