Objectives: There are currently around 120 million rural-urban migrants in China. Elsewhere migration has been associated with increased vulnerability to mental health problems. This study was conducted to explore the mental health status and help seeking behaviours of migrant workers in Hangzhou city, Zhejiang Province, and to compare them with permanent urban and rural dwellers.

Methods: A self-completion questionnaire including items relating to sociodemographics, health and lifestyles and mental health, was completed by 4453 migrant workers and 1957 urban workers in Hangzhou city, and by 1909 rural residents in Western Zhejiang Province.

Results: The mean age of the migrants was 27 years, (male 29 years, female 25 years). They worked long hours (28% >12 h per day, 81% 6 or 7 days per week) and their living conditions were very basic. On the SF-36 mental health scale migrants had lower scores (52.4) than rural residents (60.4, P < 0.0001) but scored higher than urban residents (47.2, P = 0.003). The difference between urbanites and migrants disappeared after adjustment for confounders (P = 0.06). Independent predictors of better mental health status among migrants were being unmarried, migrating with a partner, higher salary, good self-reported health and good relationships with co-workers. There were small significant differences in suicide ideation and attempts between the three groups with suicide ideation commonest in migrants and suicide attempts most common in the rural population. Fewer than 1% across all three groups had received any professional help for depression or anxiety.

Conclusion: Rural-urban migrant workers in this part of China are not especially vulnerable to poor mental health. This may result from a sense of well being associated with upward economic mobility and improved opportunities, and the relatively high social capital in migrant communities.