Objectives. To describe mental health status in native and non-native Swedish-speaking pregnant women and explore risk factors of depression and posttraumatic stress (PTS) symptoms. Design and setting. A cross-sectional questionnaire study was conducted at midwife-based antenatal clinics in Southern Sweden. Sample. A non-selected group of women in mid-pregnancy. Methods. Participants completed a questionnaire covering background characteristics, social support, life events, mental health variables and the short Edinburgh Depression Scale. Main outcome measures. Depressive symptoms during the past week and PTS symptoms during the past year. Results. Out of 1003 women, 21.4% reported another language than Swedish as their mother tongue and were defined as non-native. These women were more likely to be younger, have fewer years of education, potential financial problems, and lack of social support. More non-native speakers self-reported depressive, PTS, anxiety and, psychosomatic symptoms, and fewer had had consultations with a psychiatrist or psychologist. Of all women, 13.8% had depressive symptoms defined by Edinburgh Depression Scale 7 or above. Non-native status was associated with statistically increased risks of depressive symptoms and having ≥1 PTS symptom compared with native-speaking women. Multivariate modeling including all selected factors resulted in adjusted odds ratios for depressive symptoms of 1.75 (95% confidence interval: 1.11–2.76) and of 1.56 (95% confidence interval: 1.10–2.34) for PTS symptoms in non-native Swedish speakers. Conclusion. Non-native Swedish-speaking women had a more unfavorable mental health status than native speakers. In spite of this, non-native speaking women had sought less mental health care.