Introduction: Autistic Spectrum Disorder (ASD) is often comorbid with Obsessive Compulsive Disorder (OCD). But to what extent can obsessional symptoms in individuals with ASD be considered “genuinely” comorbid OCD – or are there other mechanisms that are related to ASD? Which mechanisms in OCD with and without ASD share common features? People with ASD have a cognitive profile characterized by “mindblindness”; the antecedent is often referred to in terms of not knowing how to perform or behave and this is the cause of discomfort. This raises the question whether individuals with ASD and comorbid OCD share the same cognitive elements of responsibility interpretation and the same fear of causing harm as individuals who merely have OCD.Objective: The aim of the present study is therefore to evaluate the extent of responsibility interpretation in individuals with OCD alone compared with people experiencing OCD in the context of ASD.Methods: Two instruments, the Responsibility Attitude Scale (RAS) and the Responsibility Interpretations Questionnaire (RIQ), were administered to three groups of participants: (i) individuals diagnosed with OCD (n = 32); (ii) individuals with ASD and OCD (n = 19); and (iii) non-clinical control participants (n = 23).Results: Results indicate significant differences in all measures of responsibility belief (interpretation of obsession and assumption of responsibility) between the OCD-only group and the two other groups.Conclusion: The conclusion is that OCD in people with ASD is not as “genuine” as in people with only OCD, according to cognitive behavioral theory of OCD.