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.