Abstract: For the requirement of the VR application with complex behaviors and based on the analysis and comparison of some modeling languages, a language model of complex behavior is proposed, which can represent the control relations of behaviors and their time constraints. And an algorithm of virtual environment computing for complex behaviors is also proposed. YHVML, the modeling language of distributed VR software development platform YHVRP, implements the model, whose run\|time environment implements the computing algorithm for complex behaviors .The least\|laxity\|first （LLF） strategy is adopted to schedule behaviors dynamically to ensure the real\|time interactivity and fidelity of VR application. Finally, an instance shows the efficiency of the related model and algorithm.