The present study seeks to estimate the strength of the association between exposure to lifetime traumatic events and gambling problems while accounting for the potential contribution of psychiatric disorders, genetic factors, and family environmental influences. In 2002, structured diagnostic interviews were conducted with 1675 male twins to obtain data on exposure to traumatic events and pathological gambling. Multinomial regression tested for associations between each traumatic event and three levels of problem gambling (1-2 symptoms, at risk; 3-4 symptoms, problem gambling, and 5 or more symptoms, pathological gambling). Analyses of data from twin pairs discordant for gambling behavior controlled for genetic and family environmental factors. After adjustment for covariates, child abuse (relative risk [RR]=2.31), child neglect (RR=5.53), witnessing someone badly hurt or killed (RR=2.83), and physical attack (RR=3.39) were associated with pathological gambling. Genetic and family environmental factors significantly contributed to the association between exposure to traumatic events and one or more symptoms of problem gambling. Exposure to childhood and lifetime traumatic events are significantly associated with problem and pathological gambling. These associations are partially accounted for by psychiatric covariates and genetic and family environmental factors.