This study examined the predictors of problem gambling in UK veterans. An online survey was completed by 1,037 veterans and 1,148 non-veterans who were matched on age and gender. Veterans were at higher risk of problem gambling than non-veterans. Various sociodemographic, military service, mental health, and gambling characteristics were found to be predictors of problem gambling in veterans. Of note, gambling to cope with stress was a strong predictor of problem gambling. Being diagnosed with likely PTSD or complex PTSD also increased the risk.