Escape behaviour of the anchovy (Engralius japonica, total length 4-7cm) at the inside wing net and bag net in the anchovy boat seine was observed by underwater video camera in order to clarify the relationship between visual stimulus of the gear or relative water flow inside gear and reacting behaviour. The vertical attenuation coefficient of underwater illuminance in the offshore of Keoje island and Tongyoung was ranged from 0.24 to 1.03 and it could be affect visual range and visual contrast of the fishing gear. The relative water flow at the joint part between inside wing and bagnet while towing was 1.5 times higher than at the middle part of inside wing or fore part of bag net, but it was estimated under than maximum swimming speed of 4-7 cm anchovy. The mean escaping number of anchovy from end part of inside wing of 30 cm mesh to out side for a minute within visual range of video camera was 455 and anchovy swimming forward from bag net through flapper was 308. These results revealed anchovy could escape as voluntary response in spite of higher visual stimulus or higher water flow.