Objective: Traumatic brain injury (TBI) has been implicated as a risk factor for the later development of Alzheimer Disease, although some studies have reported this association only in males. TBI has also been associated with earlier onset of mild cognitive impairment (MCI), although little is known about potential gender effects in this population. As such, we examined the effect of gender on age of MCI diagnosis with and without a history of TBI. Method: MCI subjects were obtained from the National Alzheimer's Coordinating Center Uniform Data Set and stratified by gender. Subjects were categorized based on lifetime self-reported TBI with loss of consciousness (LOC) more than one year prior to MCI diagnosis (TBI+ female = 114; male = 182) and compared to subjects without a history of TBI (TBI- female = 1359; male = 1329). Age of diagnosis was examined between the TBI+ and TBI- groups using one-way ANOVA. Results: Education, race, and apolipoprotein E-e4 status were similar across groups for females and males. Female TBI+ subjects (M DxAge = 72.8, SD = 10.6) were diagnosed with MCI an average of 1.9 years earlier than those without TBI (M DxAge = 74.7, SD = 9.0; p < .05). Male TBI+ subjects (M DxAge = 72.1, SD = 9.4) were diagnosed with MCI an average of 2.6 years earlier than those without TBI (M DxAge = 74.7, SD = 8.5; p < .001). Conclusion: History of TBI was associated with an approximately 2 year earlier diagnosis of MCI in females and males. These findings suggest TBI may be associated with earlier expression of cognitive decline regardless of gender, and supports mounting evidence for TBI as a risk factor for later life cognitive decline.