Ship has become inseparable part of international trading scheme which involves large scale commodities in export-import. During its operation to reach the designated destination, vessel traffic and geographical condition are possibly causing the accidents on the ship. As chain of reaction, commodities/cargoes can be spilled which influence surroundings. Emergency situation is certainly taking place if the cargo is classified as dangerous item, such as chemical compound and crude/product oil. Effect to environment can be immense, which includes living ecosystems and species. This work presents a series of discussions related to environmental casualties due to accidents which take place in maritime territory. Statistical data of accidental phenomena in the recent century is summarized. Infamous accident of the Exxon Valdez is considered as the prime case, and the environmental casualties are discussed which can be further references for maritime countries in regulation planning for prevention and mitigation accounting for oil spill. Keywords: Maritime accident, Exxon valdez, Oil spill, Evacuation strategy, Environmental impact