Long-term monitoring of the rainforest dynamics, according to various kinds of disturbance, has been undertaken in French Guiana since 1984, on the Paracou site, 50 km north-west from the spatial center of Kourou. The great amount of detailed and spatialised data gathered on twelve plots, 9 ha each, and dealing with more than 46 000 trees, allowed us to build models of forest dynamics. One of them is an individual based spatially explicit model, the development of which led us to describe as precisely as possible the different components of the dynamics: growth, mortality and in growth, at an individual scale, before including them inside a simulator. The object of the paper is to present the results obtained with the growth component. It has been developed using the " potential x modifier " philosophy, but adapted to take into account the rainforest conditions. It presently predicts the mean annual diameter growth of trees, according to their diameter, local environment described through competition indexes, and species they belong to. Trials to take into account pedological and topographical information remained unsuccessful due to the lack of accuracy of the available data. Problems encountered and remaining to improve this model are discussed.