YouTube is one of the most well-known and widely accessed websites worldwide, thus having a powerful pedagogical potential. Nonetheless, the quality and the veracity of some YouTube videos are questionable. Doubts regarding the trustworthiness of factual content is a controversial factor that needs to be taken into account, especially when addressing public health issues. For this reason, the main objective of this work is to analyze the content of the most viewed videos in Spanish on YouTube related to autism spectrum disorder (ASD). To carry out this research, the terms "autism AND education", "autism AND intervention", and "autism AND cure" were used (in Spanish). The analysis of these searches results indicated that videos included in the "cure" category are shorter, and less valued by internet users, obtaining the lowest ratings on the "Patient Education Materials Assessment Tool" for audiovisual materials (PEMAT-A/V), in addition to present therapies that are in fact more harmful than videos in other categories. In general, videos containing recommendations for therapies that are harmful are the ones that have received most views, along with the videos that include alternative non-harmful therapies. Practical implications of these findings and recommendations for further research are discussed.