Abstract: This paper introduces the major steps and principle of drawing the measured stratigraphic section by using the circular arc method with a microcomputer.The concept of the sector is introduced in the method;thus the method can be applied to more complex stratigraphic sections.Detailed steps are given about dealing with the faults and dikes in a section linking stratal lines in several sectors,drawing wavy lines and special line types of metamorphic rocks ,determining the position,scale and direction of mineral patterns and symbols.