As East Asians are, on average, less happy than those in economically developed Western nations, more insights regarding the associations between work, income and happiness are needed. This study analyzes data from the 2010 East Asian Social Survey to investigate these associations in China, Japan, South Korea and Taiwan, and is framed in a similar context as previous studies that utilize data from Western nations and through the lens of social comparison theory. Path analysis is used to model the associations between happiness and its predictors while taking correlations between the predictors into account. Results show that working hours are negatively associated with happiness in China, Japan and Taiwan, but such an association is not observed in South Korea. At the same time, relative income is significantly associated with happiness in all four East Asian nations, but it only mediates the association between working hours and happiness in China. These results suggest that careful consideration of economic and labour policies are critical to promote the happiness of East Asian workers. Findings from this study are useful for further inquiries with regard to specific explanatory factors of the associations between working hours, relative income and happiness in East Asia.