The aim of this study is to understand the nature and characteristics of mental-health-related stigma among Japanese people. We searched relevant studies in English or Japanese published since 2001 using MEDLINE and PsycINFO, and found 19 studies that examined mental-health-related stigma in Japan. Regarding knowledge about mental illness, reviewed studies showed that in the Japanese general population, few people think that people can recover from mental disorders. Psychosocial factors, including weakness of personality, are often considered the cause of mental illness, rather than biological factors. In addition, the majority of the general public in Japan keep a greater social distance from individuals with mental illness, especially in close personal relationships. Schizophrenia is more stigmatized than depression, and its severity increases the stigmatizing attitude toward mental illness. The literature also showed an association between more direct social contact between health professionals and individuals with mental illness and less stigmatization by these professionals. Less stigmatization by mental health professionals may be associated with accumulation of clinical experience and daily contact with people who have mental illness. Stigmatizing attitudes in Japan are stronger than in Taiwan or Australia, possibly due to institutionalism, lack of national campaigns to tackle stigma, and/or society's valuing of conformity in Japan. Although educational programs appear to be effective in reducing mental-health-related stigma, future programs in Japan need to address problems regarding institutionalism and offer direct social contact with people with mental illness.