an important component of deep-water net cageis the most complex loading part of cage system. Studying the movement characteristics of cylinder net exposed to current is a key to deeply understand the properties of withstanding strong current about net cage. In this papera numerical model for 3-D nets in steady current was set up. To verify the validity of the numerical modelmodel test results made by other authors were cited and compared with the numerical results. The numerical results for the drag force on the net and the net deformation agreed well with experimental ones. On the basis of that1=400 kg and five kinds of current velocitiesthe displacement and the pitch angles of the net bottom were calculatedand the influences of current velocity and weight size on the movement and deformation characteristics of the net were discussed. The calculated results indicated that the increasing of current velocity could intensify the net deformation. The volume reduction rate of the net with weight mode GW₁ when =0.75m/s reached more than 50%. For different weight modes and current velocitiesthe horizontal displacement of the fore point at the bottom of the net was great than that of the rear onewhile the vertical displacement of the fore point was less than that of the rear one. With current velocity increasingthe displacement difference between the two points had become more obvious. When the weight increasesthe pitch angles of the net bottom and the volume reduction rate of the net could all decrease accordingly.