The existing fisheries managers ignored the fishery environment changes, have built competitively vessels of efficiency superiority with related corporations, and have captured indisciminately fisheries resourecs. The economical engine horsepower selection model for fishing vessels shorter than 24m is developed. Also, the economical engine horsepower selection model system is verified by the existing vessels, and the optimum vessel scale and engine horsepower classified by the type of fishery and scale are proposed.