With the continuous development of computer technology, people pay more and more attention to the drawing process, and gradually improve it when designing and developing new software. This paper will study based on computer-aided graphics rendering system. Firstly, this paper introduces the concept and characteristics of chemical automatic drawing, then studies the straight-line algorithm and arc algorithm in drawing based on computer technology, designs and develops the framework of chemical automatic drawing system, and tests the performance of the system. Finally, the test results show that the system has strong response load, stable system performance, good stability and high sensitivity. These reasons make the automation technology in the chemical process operate effectively in the actual work, so as to improve the production efficiency and product quality of the enterprise.