Poor reciprocity is a defining feature of an autism spectrum disorder (ASD). In the current study, we examined the reliability and validity of the Interactive Drawing Test (IDT), a new instrument to assess reciprocal behavior. The IDT was administered to children and adolescents with ASD (n = 131) and to a typically developing group (n = 62). The IDT had excellent inter-rater reliability and moderate to good test–retest reliability. The results showed clearly distinctive response patterns in the ASD group compared to the typically developing group, independent of verbal IQ and age. Convergent validity of the IDT was low. Sensitivity and the predictive accuracy of the IDT for detailed levels of reciprocal behavior in autism are discussed.