BackgroundPsychological distress has been known as a major health problem among farmers across the world. In Vietnam, approximately 50% of farmers have lived in rural and mountainous areas. Yet, little has been known about how psychological distress impacts mountainous farmers’ health.ObjectivesThis study aimed to examine the prevalence and risk factors related to psychological distress among mountainous farmers in Vietnam.Design and settingA cross-sectional study was performed from August to September 2018 in Moc Chau district, Vietnam. A structured questionnaire and face-to-face interviews were used for data collection.ParticipantsA random sample of 197 farmers aged at least 18 years, spoke Vietnamese, was not suffering from severe diseases and residing in Moc Chau at the time of the survey were recruited.Primary and secondary outcome measuresThe Kessler Psychological Distress Scale (K6) was employed to measure psychological distress. The tobit and logistic regressions were applied to indicate associated factors.ResultsThe prevalence of psychological distress was 38.2% (95% CI 31.3% to 45.5%). Having a greater comorbidities (OR=6.17; 95% CI 1.44 to 26.43), drinking alcohol (OR=3.86; 95% CI 1.02 to 14.59) and obtaining health information from health workers (OR=3.77; 95% CI 1.22 to 11.66) were positively associated with the prevalence of psychological distress. By contrast, being overweight (OR=0.29; 95% CI 0.09 to 0.93), adopting books as the primary source of health information (OR=0.11; 95% CI 0.01 to 0.8), and receiving a higher number of home visits by community health workers (CHWs) (OR=0.38; 95% CI 0.14 to 0.99) were negatively associated with the prevalence of psychological distress.ConclusionThis study highlighted a high prevalence of psychological distress among mountainous farmers. Providing routine psychological and physical health screening, developing CHWs to provide clinical support and raising health awareness are critical implications for reducing psychological distress in this population.