In Film Theory, the debate about the canon is stuck in the creation of lists by professionals or critics. In contrast to this, the Polysystem Theory proposes tools for developing alternative methodologies that lead us to a clear understanding of the canonization process. The analysis of the factors of the cultural system makes possible a precise and true approach to this phenomenon, where the mentioned lists are only additional elements present in this context, and the intersystemic interference becomes the most sophisticated sign of canonization.