The influence of multiple mild traumatic brain injuries (mTBIs) on neuroelectric and task performance indices of the cognitive control of action monitoring was assessed in individuals with and without a history of concussion. Participants completed a standard clinical neurocognitive assessment and the error-related negativity of the response-locked event-related brain potential and task performance were measured during a modified flanker task. The findings suggested that those individuals with a history of mTBI demonstrate certain failures in cognitive control, and indicated that a greater number of mTBIs may relate to poorer integrity in the evaluation or signaling for control during instances of conflict. Given that these neuroelectric and behavioral differences exist in the absence of disparities in standard clinical assessment, the findings suggest that measures of cognitive control may be more sensitive to signs of chronic cognitive dysfunction resulting from mTBI.