In today's world, a good command of more than two foreign languages is a commonplace necessity. However, this is not the case for the majority of language learners in Iran. The foreign languages which could be of any avail to them are neither close to Persian nor have any daily social usage. The present research aims at promoting this linguistic ability by improving the methods of simultaneous teaching of two foreign languages in Iran. Through studying the concept of bilingualism and acquiring a more profound insight into simultaneous teaching, a plan was designed for teaching 20 sessions of English and French to two groups: Group A comprised of beginner learners in both languages and Group B of intermediate learners in English who were beginners in French. Thirty-six participants took part in the project. Twelve were in the simultaneous classes and 24 in the Control Groups, assigned into four groups of six based on language proficiency levels. The following results were reached based on the average grades of the final exam and the placement tests (given both before and after the course). On the whole, Groups A and B obtained higher averages than the Control Groups. The findings of this study suggest that not only simultaneous learning is not an impeding factor but also it reinforces learning of the two languages. We hope that this research will be a first step towards a more extensive study on a national scale for Iranians and especially for children to be multilingual.