A total of 212 winter perch specimens sampled by commercial hand line in thewaters off Pescadores during August 1993-August 1994. The fork length of thewinter perch under 250 mm were all females; but over 250 mm, males becamedominant. Age determination was made by means of scale reading. Judging from thededuction of the monthly change of marginal increment, the annulus is formedonce a year during the period of October-December.