Objective: Emotion regulation difficulties have been associated with traumatic event exposure, posttraumatic stress disorder (PTSD) symptoms, and associated sleep disturbances. Dispositional mindfulness, the tendency to experience the present moment, on purpose with acceptance and nonjudgment, can be conceptualized as adaptive emotion regulation. While dispositional mindfulness has been associated with adaptive posttrauma outcomes, it has not been examined in relation to trauma sequelae, such as sleep disturbance. The current study aimed to expand upon previous research to further explore the relationship between dispositional mindfulness and trauma sequelae. Method: Participants (N = 217) were recruited using Amazon’s Mechanical Turk to complete online surveys assessing PTSD symptom severity (PTSS), sleep disturbance, emotion regulation difficulties, and mindfulness. Results: After controlling for PTSS, the results suggest that dispositional mindfulness is associated with lower frequency of PTSD-related sleep disturbance and better sleep quality (daily disturbances). Additionally, the results suggest that specific dispositional mindfulness domains remain significant when emotion regulation difficulties domains were included in the model. Conclusions: Future research should further examine this relationship to inform mindfulness-based interventions for PTSD and sleep disturbance. (PsycInfo Database Record (c) 2022 APA, all rights reserved)