A method for generating typographical line is provided. In the present method, an asymptote of an upper or a lower edge of a line of printing words is obtained first. Then, two typographical lines of the other edge of the line of printing words are obtained according to the asymptote. Two typographical lines of the present edge of the line of printing words are obtained based on the previously obtained typographical lines. Finally, the relations of these typographical lines and edge reference points of the line of printing words are used for removing useless typographical lines. Therefore, the typographical lines obtained by the present invention can provide the means of recognizing word direction, large or small character writing, and punctuation marks, so as to increase the efficiency and accuracy of character recognition.