The ability to correctly divide the ridges into “ridges” and “grooves” is the key to the independent cultivation of agricultural machinery in the ridges. Although the color and texture of the ridge row show diversity depending on the soil and the way of trenching, the scale of the ridge row in the image gradually decreases from near to far. Based on this feature on the ridge scale, this paper proposes a multi-scale segmentation algorithm for ridge row. The method uses the Gaussian difference pyramid structure to construct the multi-scale feature set of ridge rows. Then, according to the distribution of ridge rows in different scales, the image in multi-scale feature set is centralized and saturated with gray value. Finally, each feature image is segmented and weighted respectively to divide the image into “ridge area” and “ditch area”. Experiments on 40 ridge rows show that the proposed algorithm can effectively segment ridge rows in different scales, and effectively suppress the noise generated by local soil characteristics.