The anxiety levels of students with autism spectrum disorder (ASD) over the period of transition from primary to secondary school are investigated. A repeated measures design and an adapted version of a self-report measure, the Spence Children's Anxiety Scale (SCAS), are used to compare the anxiety levels of eight students before and after the transfer. Analysis at the individual level of the sub-scale scores using the adapted SCAS against the standardised norms in two studies involving community samples reveals a mixed picture. These findings suggest that individual differences are a significant feature. Limitations of the research and possible avenues for future research are considered. Implications for supporting students with ASD in schools are outlined. (Contains 6 tables.)