In this paper, we present our work on a level of detail(LoD) technique for human-like face models in virtual environments. Conventional LoD techniques have been adapted to allow facial animation on simplified geometric models. This includes optimization on both geometry, and animation parameters. Simplified models are generated in a region-based manner in consideration with the mobility of each region. The animation process is decomposed into two sub-processes and each step is optimized. In the MPA(Minimum Perceptible Action) level optimization, a hierarchical structure was devised for the multi-level animation model. The deformation level is simplified by reducing the number of control points. During runtime, the level of animation is selected in combination with the viewpoint information the level of geometry. Keywords : levels of detail, virtual humans, real-time facial animation.