The movement ranges and diurnal behavior of the rockfish (Sebastes schlegeli) sonic tagged externally were measured by the acoustic telemetry in the marine ranching area of Tongyoung on 20 to 26 March and 4 October to 3 November, 2003. The results of study are as follows: 1. Two cage cultured fishes (body length: $30-34{cal}cm$) were released the point where located approximately $250{cal}m$ from the caught point on 30 March, 2003. They moved to the south $500{cal}m$ away Sojangdudo and stayed within a $500{cal}m$ radius of the position during the study. 2. Three wild fishes (body length: $28-32{cal}cm$) were released around the caught point on 4 and 8 October, 2003. It was often measured that tagged fishes moved out the $500{cal}m$ radius of released point for a week after release. After several days, the movement range tended to be reduced. Finally, they stayed within the $250{cal}m$ radius of released point. 3. There was no significant difference of diurnal behavior of the rockfish between the cage cultured and the wild fishes. The movement range, however, for the night-time was a little wider than for the day-time.