We identified, summarized, and appraised the certainty of evidence for 12 studies investigating the use of music therapy for individuals with autism spectrum disorder (ASD). The studies were summarized in terms of (a) participant characteristics, (b) dependent variables, (c) procedures, (d) results, and (e) certainty of evidence. A total of 147 participants aged 3 to 38 years were included in the 12 studies. Dependent variables included: (a) decreasing undesirable behavior, (b) promoting social interaction, (c) improving independent functioning, (d) enhancing understanding of emotions, and (e) increasing communication. Music therapy included the use of specific songs with lyrics related to target skills as well as musical improvisation. Outcomes were positive for 58 % of the studies and mixed for 42 % of the studies. Certainty of evidence was rated as conclusive for 58 % of the studies. The existing literature suggests that music therapy is a promising practice for individuals with ASD, but additional research is warranted to further establish its generality and the mechanisms responsible for behavior change.