Nurses are at a high risk for work-family conflict due to long and irregular work hours and multiple physical and psychosocial stressors in their work environment. Nurses report higher rates of depressive symptoms than the general public, leading to a high rate of burnout, absenteeism, and turnover. Work-family conflict is associated with negative consequences in nurses including physical illnesses and mental disorders. CONCLUSIONS Past research on this topic has not examined the mechanisms for the effect of work family conflict on depression. Studies rarely examine the influence of health behaviors such as sleep in explaining this association. Our study identified significant association of sleep disturbances with both work-family conflict and depressive symptoms in nurses. Our main contribution is reporting the important role of sleep disturbances in translating the effect of work-family conflict on depressive symptoms among nurses. CONCLUSIONS Nurses need to receive training in best practices for maintaining their own sleep and mental health. Organizations should include sleep health education and training in workplace health programs. Evidence-based interventions to promote healthy sleep practices such as cognitive behavioral therapy and complementary and integrative approaches should be evaluated for their effectiveness in addressing the impact of work-family conflict on the mental health of nurses. Healthcare organizations should incorporate mental health services as part of their Employee Assistance Program for nurses and include psychological and sleep disorders screening, counseling, and follow-up. Introduction Depression has been identified as the leading cause of disability worldwide. Nurses report higher rates of depression than the general public. Work-family conflict is challenging for nurses and may lead to depression and poor health. However, the mechanisms for the effect of work-family conflict on depression have not been well understood. Aim The objective is to use a cross-sectional design to examine the role of sleep disturbances in the association between work-family conflict and depressive symptoms in nurses. Methods Questionnaires, measuring working conditions, work-family conflict, sleep disturbances and depressive symptoms were collected from 397 nurses at a not-for-profit community hospital in the north-eastern United States. Results We observed a significant association between work-family conflict and depressive symptoms (β = 2.22, p < .001) among nurses. Sleep disturbances partially mediated this association by 40.54%. Discussion Sleep disturbances play an important role in translating work-family conflict into depressive symptoms. Implications Evidence-based interventions to promote healthy sleep practices should be evaluated for their effectiveness in addressing the impact of work-family conflict on mental health. Organizations should include sleep education and training as a component of workplace health promotion and employee assistance programmes to mitigate the effect of work-family conflict and promote overall health in nurses.