A high-quality line structure extraction method based on cartoons belongs to the image processing technology field. The method comprises steps of, a, image pre-processing: removing image noise by a bilinear filtering method; b, reinforcing the line structure by a second-order Gauss template convolution method; c, obtaining isolated line points by restraining non-maximal values on the reinforced image; d, line structure acquiring: selecting a biggest-response point as an initial enlarging point by a best and prepreference manner, enlarging the point to the two sides so as to obtain the line structure with line strips; e, repairing the result based on semantic information. According to the method, vector elements with more semantic information can be obtained, and inter-frame continuity and inter-frame association quality can be increased during the vectorization process of the cartoons.