The relationship between trauma and mental health is well-documented, but how trauma experienced during a forceful migration and ongoing daily stressors affect the mental health and quality of sleep of elderly refugee populations is scarce. We recruited 207 forcibly displaced Myanmar nationals, aged 60 to 100 years, resettled in Cox's Bazar and Bhasanchar, Bangladesh. The participants completed the Questionnaire for Traumatic Events Assessment and the Brief Daily Stressors Screening Tool to report the types and frequency of traumatic incidents they were exposed to and their ongoing general stressors. We also assessed their religious coping, sleep quality, PTSD, depression, and generalized anxiety using standardized, Rohingya-translated tools. Hierarchical multiple regression analyses revealed that exposure to trauma and daily stressors significantly predicted PTSD, depression, and sleep quality after controlling for the participants' age and gender, in which daily stressors appeared to be a stronger predictor. Parallel mediation analyses showed that daily stressors mediated the predictive relationship between trauma and PTSD positively; however, negative religious coping mediated this relationship negatively. Daily stressors also positively mediated the trauma-depression and trauma-sleep quality relationships. The results indicate that practitioners should address daily stressors, besides past trauma, while devising any intervention programmes for refugee mental health and their sleep disturbances.