Previous research indicated that there exist severe disabilities in non-literal meaning comprehension among people who are diagnosed with Autistic Spectrum Disorder (ASD). These defects were explained from various dimensions including social cognition and language information processing. Social cognition defects and disability of early language information processing maybe originated from the same neural basis because brain development defects have been found among the people with ASD. These development defects cause their disability of social cognition and language information processing and further affect their non-literal meaning comprehension. In view of the experience of past research, metaphor is an appropriate perspective to explore the defects of non-literal meaning comprehension. For instance, a low efficiency of ASD metaphor semantic integration may be caused by right hemisphere dysfunction or underconnectivity between the hemispheres or brain regions which are the results of cerebral white matter or other brain structures development dysfunction. All above defect of brain structure or brain function impair different kinds of metaphors or other non-literal meaning comprehension. Recent studies explored the brain defects on metaphorical semantic comprehension from neural physiological level and mainly among the patients with Asperger's syndrome (AS). However, inconsistent conclusions have been made among the people diagnosed on High Functioning Autism (HFA). Furthermore，the research participants have been limited to children and little is known on metaphor semantic integration of adults with HFA. In order to examine the neural physiological features of metaphor semantic comprehension among adults with HFA and to make proposals to other research of non-literal meaning comprehension, the present study recruited 20 adults with HFA (mean ages = 19.95 years) and their 20 typically developing peers(mean ages=19.40 years) who were matched on IQ. Event Related Potential (ERP) was used to investigate the metaphorical semantic processing of four types of sentences including novel-metaphor sentences, conventional-metaphor sentences, literal sentences, and error sentences. All participants were asked to perform a semantic judgment task that required them to decide whether the sentences showed on the computer screen conveyed a meaningful expression or not as quickly and accurately as possible. The results showed that: HFA adults can comprehend metaphor semantic ultimately with a long response time and a normal accuracy. In the typically developing group, the largest N400 amplitude of error sentences and a right hemisphere advantage effect were found. Novel metaphor sentences had smaller N400 amplitude comparing to error sentences but N400 of the former was still larger than the conventional metaphor sentences and literal sentences. This result suggests that the error sentences semantic integration is most difficult among the typically developing group. A different pattern was observed in the HFA group, novel metaphor elicited the largest N400 amplitude, which was followed by error sentences, conventional metaphor sentences, and literal sentences. No lateralization effect was found on novel metaphor sentences. The present study suggests that the semantic integration ability in metaphor comprehension among HFA adults is relatively intact, but a different processing pattern was found comparing to typically developing peers. This special processing pattern may attribute to right hemisphere dysfunction or poor connectivity among different brain areas or structures. Key words Adults with high Functioning Autism; non-literal meaning; metaphor; ERP; N400