土壤调查中常常需要解决曲面拟合问题，即根据有一定分布的有限个样本网络点数值（比如高程、地下水深度、土壤ｐＨ值等），计算研究区域中所有网格点的数值。这是一个经典的数学理论问题。本文将分形理论与数字滤波（数字信号处理）方法有机地结合起来，给出一种新型的曲面拟合计算方法，该算法可以适应研究区域中存在有隔离断裂曲面的复杂情况。 It is often necessary to solve the problem of surface fitting in soil surveys by calculating the number of all grid points in the study area based on a finite number of sample network points (eg elevation, groundwater depth, soil pH, etc.) that are distributed over a certain area. This is a classic mathematical theory. In this paper, the fractal theory and the digital filtering (digital signal processing) method are organically combined to give a new method for calculating the surface fitting, which can adapt to the complex situation that there exists an isolated fracture surface in the study area.