Moral injury (MI) refers to the distress experienced when people do, or do not, do something that goes against their morals or values. It can also occur when people perceive that their values have been betrayed. MI is associated with several mental health conditions, including posttraumatic stress disorder (PTSD), depression, and anxiety. A potential risk factor for MI may include difficulties with emotion regulation (ER). Difficulties with ER refers to the ability to manage emotions. It is associated with the same mental health conditions linked to MI, including PTSD. The purpose of this study was to examine whether difficulties with ER were associated with MI in a Canadian military personnel and Veteran sample. Participants completed several questionnaires assessing for MI, difficulties with ER, and other mental health symptoms, such as PTSD, while they were inpatients at a psychiatric hospital. It was found that MI and perceived betrayals were associated with symptoms of PTSD. Symptoms of PTSD, depression, and anxiety were also associated with one another. Difficulties with ER were also associated with symptoms of PTSD, depression, and anxiety but were not related to MI. The findings serve as a first step in examining potential risk factors of MI.