: Mild cognitive impairment (MCI) is an early stage of cognitive decline associated with normal aging and dementia. Harmful behavioral activities, mental health issues, and chronic diseases that commonly manifest after retirement may predispose military veterans to MCI. Therefore, a cross-sectional study was conducted among veterans who lived in the urban city of Kuala Lumpur, Malaysia to determine the prevalence of MCI and its associated factors. A total of 406 male veterans with a mean age of 61.5 years old participated in the study. Face-to-face interviews were conducted to obtain information on sociodemographic, behavioral activities, and health-related conditions. All participants underwent cognitive tests using the Bahasa Malaysia version of the Montreal Cognitive Assessment (MoCA-BM). The results showed that the prevalence of MCI was 21.4%. A logistic regression model revealed that low physical activity (adjusted odds ratio (aOR) 10.29), hypertension (aOR 2.22), lower education level (aOR 2.98), subjective memory difficulty (aOR 3.61), and subjective concentration difficulty (aOR 3.95) were associated with a higher likelihood of MCI. In addition, those aged 60 years and above, as well as those in the non-officer group, were associated with a higher risk for MCI with aOR 4.57 and 4.59 respectively. In conclusion, inactivity and hypertension are preventable risk factors MCI. Therefore, military veterans must be encouraged to practice a physically active lifestyle after retirement to maintain a healthy cognitive level..