Purpose <p>The Royal Netherlands Marechaussee, a branch of the Dutch Military, is characterised by a diverse range of mentally and physically demanding occupational tasks. The employability of the personnel depends on the balance between occupational demands and personal resources, which can be measured through the work ability score. Therefore, this study investigates personal and work-related determinants of work ability in a branch of the Dutch Military.</p> Methods <p>We gathered cross-sectional data through a survey distributed among all operational Royal Netherlands Marechaussee personnel (n: 7,658). We used binomial logistic regression analysis to estimate the relationship between determinants in four domains (i.e., personal, workload, work characteristics, and work experience) and the dichotomised work ability scores (poor to moderate vs. good to excellent).</p> Results <p>The survey had a 20% response rate with 1538 respondents. Our study included a slightly higher percentage of reservists and civilians than the Royal Netherlands Marechaussee’s workforce. Forty per cent of participants rated their work ability as poor or moderate. Good or excellent work ability was related to older age (&gt; 50 years compared to &lt; 29 years), lower physical workload, no shift work, less fatigue, more autonomy, task clarity, and social support.</p> Conclusions <p>We found that 40% of survey respondents rated their work ability as low or moderate. In the future, factors like shift work, autonomy, task clarity, and social support may be used to improve work ability in this population.</p>