Early ASD screening has the potential to reduce delays between initial parental concerns and diagnosis, and promote early intervention. The aim of this study was to validate the M-CHAT on a French population sample of 24 month-old children. This study included a low-risk sample of 1,227 children. A total of 20 children screened positive on the M-CHAT. Twelve out of 20 of these children received a diagnosis of ASD at 36 months, yielding a PPV of 0.60. These results add to the evidence that the M-CHAT is a useful screening instrument and further demonstrates the importance of the follow-up interview in primary care settings. This study provides French practitioners with guidelines regarding the use of the M-CHAT at 24 months.