Objective: This study aimed to determine how prejudice and attitude toward people with severe mental illness, formed through exposure to the mass media, affect discriminatory behavior toward them. Methods: Between September and November 2019, demographic data were collected using an online survey of 622 adults residing in South Korea. The scales used in this study were taken from the 2008 survey by the National Human Rights Commission of Korea. Structural equation modeling was performed for a comparative analysis of the direct and indirect effects. Results: Virtual experience through mass media exposure had a statistically significant effect on prejudice against people with severe mental illness. Direct experience had a positive influence on reducing prejudice and discriminatory behavior. The direct effects of prejudice on discriminatory behavior were significant. In terms of indirect effects, the full mediating effect of prejudice was significant for the virtual experience through the mass media-prejudice-discriminatory behavior path, and the partial mediating effect of prejudice was significant on the direct experience-prejudice-discrimination behavior path. Conclusion This study recommends more careful reporting of mental illness in the media, promoting anti-stigmatization programs that provide opportunities for direct contact between the public and people with severe mental illness.