Teachers' beliefs in certain neuromyths about neurodevelopmental disorders can negatively impact the educational inclusion of students who present them. This study aims to analyse the prevalence of neuromyths about the health and the emotional competences of people with autism spectrum disorder (ASD) in pre-service teachers; and to assess the possible contribution of university training to constructing accurate knowledge about autism. This prevalence was compared in three groups of pre-service teachers: 1st-year students, 4th-year students who will be regular teachers and 4th-year students training to be special education specialists. Additionally, it was proposed to identify the topic with the most myths (health or emotional competences) and the most frequent myths. A validated instrument was completed by 167 pre-service teachers. Overall, the 4th-year specialist group had more correct answers and fewer doubts that the 4th-year regular group, which had more correct answers than the 1st-year group. The prevalence of errors was not statistically different among the three groups. Moreover, participants answered more questions and made more errors about emotional competences in autism than about health. Among the most frequent myths are those concerning empathy or the cause of ASD. Based on these results, some implications for pre-service teacher education are discussed.