Schizophrenia patients often have a difficulty in constructing appropriate relationships with others in social situations. This impairment of social cognition is also found in autism-spectrum disorder（ASD）.To elucidate the neural basis of such commonality between these two disorders, we explored the association between Autism-Spectrum Quotient（AQ）and gray matter（GM）alterations measured by MRI in schizophrenia subjects. Schizophrenia patients showed significantly higher scores in total AQ compared with control subjects. In addition, the total AQ score in schizophrenia subjects showed significant negative correlation with GM volume in the cortical area surrounding the left superior temporal sulcus（STS）. As STS is the area which has been reported to be pathological in ASD, our findings suggest a partial neuroanatomical commonality between ASD and schizophrenia.