针对矢量GIS中点，线和面3种基本要素，在胡机点的概率密度函数及其图象和反映随机点的定位不确定性的误差区间及误差椭圆的基础上，详细阐述了基于随机过程和随机场理论所提出的随机线元，面元的概率密度函数及其图象，从几何图形角度 由于定位不确定性引起的线位误差带和面位环的构成机理。

This paper aims at the random point,line and surface in vector GIS, based on the analysis of the point's probability density function, image and the error interval, error ellipse which are induced by positional uncertainty, elaborates the random line's, surface's probability density functions and images by means of the stochastic process and random field theory, presents the proper reasons of the line's error band and surface's error donut. The visual figures according to different conditions are given.