Recently, many tools for biological pathway simulations have developed aiming deeper understanding of molecular interaction in cells. We are developing Cell Illustrator that has Petri net as a basic architecture and also Cell Animator that can output molecular action by intuitive animation. However, it was necessary to make the tag of XML to do the animation of Cell Animator and it was difficult for the user. Then, CI Builder that was making XML only by GUI operation was developed, and effectiveness was examined compared with a past method.