Abstract: Based on the characteristics of tropical rain forest, this paper establishes new measures of tree growing competition and deals with the relations of tree growing competition associated with the tree growing models. Two measures of point density in stand are introduced. One is composed of the relative height of central tree in circle sampling plot, which makes known the state of single tree growing competition. The other is the relative volume of tree crown, which the sum of that is a reflection of stand growing competition. The results show the measures can represent states of tree growing competition in tropical rain forest, as modeling variables, which can raise the estimating precision of tree growing models. This study also provides the basic theory and methods for discovering the patterns of trees growing competition and then studying the stability of sustainable system of ecology.