Previous research has demonstrated the effect of supervisor support on the job satisfaction of long-term care workers (LTCW); however, much less is known about how this effect differs among race/ethnicity or immigration groups. We examined how supervisor support mediates the associations between race/ethnicity, immigration status, and job satisfaction among nursing assistants (NAs). Data of 2749 NAs were extracted from the National Nursing Assistant Survey (2004). Findings indicated that NAs of non-Hispanic Black and other races and immigrant workers were more likely to be satisfied with their jobs compared to White and non-immigrant workers, and the associations were mediated by NAs’ perceived supervisor support. Minority or immigrant LTCW may be more sensitive to supervisory support and more grateful if they received support from supervisors. Managers should be aware of these racial differences and by being supportive they may improve NAs job satisfaction and reduce turnover rates.