This paper addresses the importance of argumentation in science education. A research project was done in order to know how a group of pre-service chemistry teachers has been prepared to promote students' argumentation. A Chemistry degree studies plan from a Colombian university was surveyed, and 18 future teachers' representations about argumentation were analyzed. Results indicate argumentation is not an explicit priority for the pre-service chemistry teachers training program studied. Additionally, future teachers showed consciousness about the necessity of being prepared to engage students successfully in argumentative activities. Nonetheless, pre-service chemistry teachers manifest not to know how to design multiple methodologies to improve argumentation. Therefore, one of the multiple proposals of solution could be the incorporation of a module that allows pre-service chemistry teachers to build their own strategies to promote argumentation.