In general, marine casualities take palace by the composite action of three elements such as waterway condition, vessel condition and man condition. One of the important characteristics of most marie casualties for small cargo vessels in maritime transportation of near-coastal and greater-coasting seas in that the same kind of casualities take place repeatedly in spite of the apprent causes, Because, it takes much time and effort for seamen to master waterway, vessel or operatin technique only to the practical and sensible level. In these days, with the development of our economy, our shiypping industry has grown and therefore the demand of marine officers has increased. This economic growth brought about undesirable situation like the evasion of seamen and frequent casualities of Korea vessels. These marine casualities are being caused mainly by the unskilfulness of operating technique as well as the bad waterway condition and ship's installation condition. Therefore, I conclude, in this paper, that the most efficient and economic preventing measures of marine casualities are seeking causes and removing them in advance under the close coperation system among all concerned parties.