This study examined whether a virtual avatar could be perceived as a real human by patients with mental disease, especially schizophrenia, as well as whether a virtual avatar could be applied to acquiring patients' behavior characteristics in a short conversation situation. The virtual avatar has been used for various applications which need to communicate with other person or to train or educate by showing humanlike behavior. Recently, many researches have shown that the virtual avatar technology has been enhanced and the avatar could be perceived like real human. A virtual avatar, standing in a virtual room, was designed for this study. Tasks to approach, initiate a talk, and answer to avatar's questions was assigned to the 11 patients with schizophrenia. As behavioral parameters in the virtual environment, the interpersonal distance and the verbal response time were acquired. In addition, the Positive and Negative Syndrome Scale (PANSS) for patients was administered in order to investigate the relationship between patients' symptomatic characteristics and behavior parameters. The interpersonal distance was negatively correlated with the negative syndrome scale, a subscale of PANSS, which is consistent with previous research reporting the relationship between interpersonal distance and a real person's image. The verbal response time, however, was not correlated with any other subscale of PANSS. After analyzing subitems of the negative syndrome of PANSS, two positive correlations were found: one was with blunted affect and the other was with poor rapport. We concluded that the virtual avatar could be perceived as a real human by schizophrenic patients and the avatar could draw the schizophrenic patients' behavior characteristics.