Introduction: Mental conditions for work among workers are related to clinical performance and influenced by colleagues within the same workplace. The aim of study was to examine the work engagement and burnout of staff midwives working on maternity and labor wards and to determine the factors related to high work engagement of staff midwives, including their immediate superiors' work engagement and burnout. Methods: A cross-sectional questionnaire survey was employed in Japan. Questionnaires were distributed to 452 midwives/nurses working on maternity and labor wards of 20 hospitals and responses from 96 staff midwives and 17 of their immediate superiors were analyzed. Work engagement and burnout (exhaustion, cynicism, and professional efficacy) were assessed by the Utrecht Work Engagement Scale and the Maslach Burnout Inventory-General Survey, respectively. To examine the association of work engagement among staff midwives with their ages, marital status and work engagement and burnout of their superiors, logistic regression analysis was conducted. Results: Immediate superiors showed significantly higher level of work engagement than staff midwives, while there was no difference in the burnout. High work engagement of staff midwives was significantly correlated with the professional efficacy (AOR 1.93, 95% CI 1.12 -3.33) and cynicism (AOR 2.01, 95% CI, 1.04 -3.90) of their immediate superiors. There was no correlation of work engagement between them. Conclusions: High work engagement of staff midwives was correlated to high professional efficacy and cynicism of their immediate superiors, suggesting that there might be crossover effects on mental conditions for work between staff midwives and their immediate superiors.