依据分形盒维数测定的原理和方法，提出了应用AutoCAD软件实现分形盒维数的简便计算方法，测定马莲河流域不同水文站的日径流过程盒维数，并对其变化特征进行了比较和综合分析，以揭示不同水文站之间分形特征的差异。结果表明：应用AutoCAD方法做日径流过程的分维计算的方法快速、准确，值得推广；马莲河流域的4个水文站的日径流过程都具有明显的分形特征，分形维数介于1～1.39之间，总体变化不大；对同一个水文站来说，不同年份的日径流过程分维值年际变化不大，存在显著的自相似性；对于同一个流域不同的水文站来说，干流的日径流过程分维值要明显大于支流的分维值，下游要大于上游，4个水文站分维值年际变化趋势基本保持一致。

Fractal dimension plays an important role in investigating the fractal features of daily stream flow. This paper proposes an estimating method of daily stream flow by using the AutoCAD according to Fractal Theory, and then, taking the four gauging stations of the Malian River as examples, calculates the fractal dimensions of the daily stream flow of four gauging stations. The result shows as follows: The method based on the AutoCAD are more facilitative compared to the traditional method; The stream flow of the four gauging stations all has distinct fractal features; The box-counting dimension varies between 1 and 1.39, and the dimension of the downstream gauging stations is higher than that of the upstream gauging stations for same water basin.