The aim of this study is to supply the basic field data and precautionary measures that was obtained from analys of troubles and failures in the main engine and its accessories of fishing vessels. In this paper, we analyzed the accidents of main engines and their accessories in fishing vessels for five years from 2000 to 2004, according to engine system, type of fishing vessels and engine power. Finally, we propose the methods to reduces the accidents of main engines and rheir accessories in fishing vessels.