This paper expatiates the notion of image fractal dimension and multi-scale fractal feature,proposes a ship target detection method based on multi-scale fractal feature.Experimental results show that the difference of the multi-scale fractal feature between artificial target and natural background is obvious.The proposed method can detect targets stable,is superior to the edge detection method,the threshold segment method and the single fractal dimension method,and is a promising detection method of the ship target.