Causes of mortality of the Eurasian otter in the Czech Republic were studied by the analysis of found carcasses. Most of the carcasses were accidentally found in the environment. Altogether 316 cadavers were analysed from 1990 to 2011. A part of the analysed data was obtained from older databases and unified. Since 2008 a single database exists and standard protocols of collection and necropsy are followed. Most of the dead bodies were found along roads (75.6%), non-violent death accounted for 3.5% of individuals, 7.9% were intentionally killed by humans and the rest (13%) died for other reasons. Despite the fact that the results are biased by several methodological problems, clear trends were revealed. Otters die more frequently at the roads with higher traffic intensity. Males are more prone to traffic mortality. The proportion of otters dying at roads has been increasing during the last years, as well as the proportion of otters illegally killed by humans.