This study investigates the effects of perceived organizational support (POS) and coworker support on the voice behavior and psychological stress of foreign workers in Macau hospitality industry. Drawing upon social exchange theory, we propose that POS and coworker support exert differential impacts on foreign workers’ promotive and prohibitive voice. We further hypothesize the negative relationships between these two types of support and psychological stress. Our hypotheses were tested by a two-wave longitudinal survey data collected from 141 foreign workers employed in four Macau hotels. The results showed that, although POS and coworker support were positively related to promotive voice, the effect of POS was comparatively stronger. Only POS had a significant and positive effect on prohibitive voice. In addition, coworker support but not POS reduced foreign workers’ psychological stress. The implications of these findings for research and practice are discussed.