Recent studies have examined non-suicidal self-injury in community and clinical samples, but there is no published research on non-suicidal self-injury in individuals with autism spectrum disorder. This lack of research is surprising, since individuals with autism spectrum disorder have high rates of risk factors for non-suicidal self-injury, including depression and poor emotion regulation skills. Using an online survey, we examined non-suicidal self-injury methods, frequency, severity, functions, and initial motivations in adults with autism spectrum disorder (n = 42). We also compared their non-suicidal self-injury characteristics to those of a gender-matched group of adults without autism spectrum disorder (n = 42). Of the participants with autism spectrum disorder, 50% reported a history of non-suicidal self-injury. This proportion is higher than non-suicidal self-injury rates previously reported for college students, adult community samples, and adolescents with autism spectrum disorder, which suggests that adults with autism spectrum disorder have increased risk for engaging in non-suicidal self-injury. Women with autism spectrum disorder were significantly more likely to endorse non-suicidal self-injury, relative to men with autism spectrum disorder. A history of non-suicidal self-injury was not related to current depression or emotion dysregulation for the participants with autism spectrum disorder. Non-suicidal self-injury characteristics among the adults with autism spectrum disorder were similar to non-suicidal self-injury in adults without autism spectrum disorder. These preliminary findings highlight the need for increased awareness and further research about non-suicidal self-injury within autism spectrum disorder.