Abstract: Structure of trees from aesthetic views is studied and a 3D modeling approach to beautify tree structure by interactive morphing is provided. It has three parts: interactively building the global model of tree level by level, selection mechanism of branches and morphing of branches. The branch stems are edited by simple morphing namely: adding, deleting, scaling, curving, rotating etc. Integral morphing provides aesthetic control to the tree by integrating simple morphing methods with aesthetic theory, such as the balance of spacing density, fashion of pruning, and a variety of tall and straight against lithe and graceful carriage. The proposed approach can be applied along with existing algorithms of tree growth or independently.