The objective of this article is to identify the beliefs of 37 prospective EFL teachers in their final year of a teacher training undergraduate degree program in two Chilean universities about the teaching of writing. At the same time, it attempts to recognize the source of these beliefs. Data were collected through a semi-structured interview. The data were analyzed through the qualitative analysis software ATLAS.ti, following the coding and categorizing of the data. The results of this study suggest that the participants possess beliefs concerning the teaching of writing production based on the use of grammar and vocabulary, the replication of text types, and the consideration of successive stages at the moment of production. At the same time, it was identified that these beliefs were acquired within the contexts of school instruction and university training. It is suggested that teacher training programs encourage new teachers to implement practices based on the communicative approach to the teaching of the skill, urging them to critically reflect on their tradition-based beliefs.