Upright orientation of a 3D object is conducive to applications such as model alignment and function recovery. However, state of art methods mainly focus on man-made models only, and some of them require much user interaction, thus lowering the processing efficiency. In this paper, a new method is proposed to effectively attain the upright orientation of an object, no matter whether it is man-made or natural. It is based on the observation that there are very few surface features on the base of the object, and so the views for watching the base will be given very low scores in view evaluation. Thus, using to the view scores, the base of the model can be found effectively to get the upright orientation of the model. To improve computation reliability, two metrics are further integrated into the method to measure the stability of model placement and the habitual viewing direction of human beings to effectively watch a model. Experimental results show that the presented method can effectively handle a variety of models, including some man-made models that cannot be well handled with existing methods, and it can run much faster than existing methods.