Inclusion Criteria:  young adult aged between 18 and 45 years who had a diagnosis of ASD from a licensed mental health or medical professional based on DSM-5; has sensory and social problems as reported by the participant and the caregiver; is motivated to participate in the treatment; is fluent in Chinese; has a full-scale IQ > 70 on WAIS-IV; scored ≧ 26 on the caregiver-reported Autism Spectrum Quotient (AQ), indicating clinical impairment associated with ASD.  Exclusion Criteria:  A history of major mental illness (e.g., bipolar affective disorder, schizophrenia, or psychosis) or neurological diseases; visual impairment and/or hearing impairment that would preclude participation in the CBT-based VR exposure program