Children who have developmental disorders that involve memorial deficits and impairments in social interaction and communication, such as Autism Spectrum Disorders (ASD), can present challenges to professionals seeking their testimony when they are victims or witnesses of a crime. Most forensic interviews involve long delays after an event, underscoring the importance of conducting experimental studies which consider the effect of delay on children's memory. In this research, fifty-nine children (age 6-15 years) with ASD (N=27) and without disabilities (N=32) were questioned about their participation in a set of activities after a two-week delay and again after a two-month delay, using the Revised National Institute of Child Health and Human Development (NICHD) Investigative Interview Protocol. A detailed coding scheme was designed to code and analyse the interviewers' utterances and the children's responses in 118 interviews. Transcripts were coded for completeness (with respect to the gist of the event), amount of narrative details, and accuracy. Results indicated that autistic children did not differ from typically developing (TD) peers on any dimensions of memory after both delays. Specifically, both groups of children provided equivalently complete accounts on both occasions. However, children in both groups provided significantly fewer narrative details about the event in the second interview, and the accuracy rates were lower. Recall prompts elicited more detailed and more accurate responses from children in both groups than recognition prompts. Although autistic children recalled fewer correct narrative details than TD peers when questioned using open-ended recall prompts, they were as accurate as TD peers in response to recognition prompts. The informativeness and accuracy of children's reports remained unchanged over time. Finally, social support was beneficial when children were interviewed for the first time but not after a longer delay. The findings indicate that autistic children can provide meaningful and reliable testimony about an event they personally experienced, but several aspects of their memory reports deteriorate over time.