This paper introduces a new method of building diverse poplar forest models, based on the "branch library" method. It introduces how to use MAXScript language to achieve the diversity of poplar model under 3ds Max environment. Compared with the simple and repetitive traditional modeling way, this method improves the efficiency of modeling with quick speed operations by the manner of code. At the same time, with age characteristic of the diverse poplar models have some application value in plant simulation and environmental animation field as well.