Recently the crowd environment in the department of the animation is necessary to the digital industry. The goal of researching a proper crowd animation is to design character animation that is defined by the reality of scenes, performance of system and interaction with users to show the crowd vividly and effectively in cyber underwater. It is important to set up the crowd behavior patterns to represent for moving crowd naturally in cyber space. In the paper, we expressed the behavior patterns for flocks of fish in cyber underwater, and compared with the number of mesh, the number of fish, the number of frame, elapsed time, and resolution and analyzed them with the fish behavior simulating system.