3维（3D）空间建模方法是3DGIS研究的核心和难点之一，是建立3DGIS的基础。迄今为止，3D空间建模方法多种多样，建模对象不同，建模方法也随之不同。根据3D空间建模研究的对象，以地球表面为界分为地理空间建模和地学空间建模两大类，并通过现有3D空间建模方法的对比研究，提出了现有3D空间建模研究的关键问题。

3D Spatial Modeling is the key to 3D GIS, and is the basis of3D GIS. All kinds of 3D spatial modeling methods are different according to the differences of modeling objects. Based on the difference of spatial modeling objects, 3D spatial modeling methods are divided into two kinds. One is Geographical Spatial Modeling, and the other is Geological Spatial Modeling. Based on the comparision and contrast of all the 3D spatial modeling methods, this paper also presents some key issues on 3D spatial data modeling.