For individuals with autism spectrum disorder (ASD), long-term outcomes have been troubling, and intact IQ has not been shown to be protective. Nevertheless, relatively little research into adaptive functioning among adults with ASD has been completed to date. Therefore, both adaptive functioning and comorbid psychopathology were assessed among 52 adults with ASD without intellectual disability (ID). Adaptive functioning was found to substantially lag behind IQ, and socialization was a particular weakness. Comorbid psychopathology was significantly correlated with the size of IQ-adaptive functioning discrepancy. These findings emphasize key intervention targets of both adaptive skill and psychopathology for transition-age youth and young adults with ASD, as well as the need for ongoing monitoring of anxiety and depression symptoms during this developmental window.