This paper proposes a novel algorithm for the automatic generation of pencil drawing from digital image. We use multi-scale edge detector to construct an outline map according to the structural importance. Using strokes as the major building blocks, we smooth the boundary and rendering outline according to the pencil sketch style. Then, tone rendering is carried out to convey both the tone and textures of the original image. Experimental results on natural scenery and architectural scenery images show that the pencil sketch drawings produced by our method are of good visual effects. Besides, the implementation require less than 1 second on the image with 400*300 pixels.