Teachers' beliefs about mathematics play an important role in the teaching of mathematics. Future teachers' views of mathematics are the basis of the quality of instruction they will deliver, as well as the teaching materials that they will present to their students and the means necessary to learn and participate in mathematical tasks. This article studies Colombian future teachers' beliefs about mathematical knowledge, taking into account two different training programmes for pre-service mathematics teachers from the same country, both of them qualify students to teach mathematics at elementary levels. Specifically, 213 mathematics graduate students and 405 normal school students from the Colombian Caribbean coast in their last term of their studies participated. Data were collected regarding four dimensions of beliefs: (i) on the nature of mathematics, (ii) about learning mathematics, (iii) about factors affecting students' achievement in mathematics, and (iv) about the quality of their training programme. Results show remarkable differences in the future teachers' beliefs depending on their training programme.