Objectives This study examined the stigma against social withdrawal syndrome (hikikomori) among mental health practitioners, and compared levels of stigma against social withdrawal syndrome versus mental illness. Methods The participants were 133 mental health practitioners (28 males, 105 females) with experience of social withdrawal syndrome that self-reported levels of stigma against social withdrawal syndrome and mental illness. Results Stigma against social withdrawal syndrome was generally significantly lower than stigma against mental illness. However, mental health practitioners tended to agree they would be reluctant to become personally involved with a person that had experienced social withdrawal syndrome (e.g., dating, hiring). Levels of stigma also differed across mental health occupations. Conclusion This study suggests although mental health practitioners may generally have less negative attitudes toward social withdrawal syndrome in the context of mental illness, that they may also have some reservations about personal interactions with individuals with social withdrawal syndrome.