OBJECTIVE To explore the relationship between social support and occupational stress. METHODS A cross-sectional survey involving 654 career people from different industries was conducted. Social support, the occupational stressors, personalities, and occupational strain were measured by using Occupational Stress Instrument. RESULTS The people from different occupations got different level of social support. Social support scores were significantly positively related to interpersonal relation, responsibility for people, responsibility for thing, advancement and participation, task identity, training adequacy, challenge, autonomy, job satisfaction, mental health, affective ambulance, positive emotion, self-esteem and coping strategy (P<0.05 or P<0.01), negatively to careers, role conflict, role ambiguity, job future ambiguity, negative emotion, depression symptoms, daily life stress and work locus of control scores (P<0.05 or P<0.01). The scores of interpersonal relation, responsibility for people, responsibility for thing, advancement and participation, task identity, training adequacy, challenge, autonomy, job satisfaction, mental health, affective ambulance, positive emotion, self-esteem and coping strategy with sufficient social support were significantly higher than those of deficient social support (P<0.05 or P<0.01). The scores of role conflict, role ambiguity, job future ambiguity, negative emotion, depression symptoms, daily life stress and work locus of control were higher than those of the latter (P<0.05 or P<0.01). Stepwise regression analysis showed that social support was the predictor of depression (R(2)>0.05). CONCLUSIONS Social support affects occupational stress largely and plays an important role in maintaining mental health of career people. The people from different occupations get different level of social support.