Abstract: A Iarge mumber of fishes in the East China Sea have the behavior of verticalmigration. In attempting to increase the fishing efficiency, a large-mesh trawlhas been designed for catching the fish in the higher level above than the normaltrawl can reach. From December 1977 to July 1978, the large--mesh trawl has beentested in comparison with the normal trawl. The result indicates that the large-meshtrawl has some advantages, such as higher trawl net mouth, less resistance, morecatches, etc.