Abstract: Age-determination based mainly on scale-reading has been made on the Chinese anchovy, Coilia ectenes Jordan et Seale, from the estuarine region of the Yangtze, the Yangtze River proper as well as certain tributary lakes. The characteristics of the annuli on the scale are described. Structures other than the scales, such as the otoliths, the pectoral fin rays and the vertebrae of this fish are also studied for comparison. Formation of new circuli peripheral to the existing annulus of the scales occurred any time from March through December.The fry and the young fish grow rapidly in body-length, the largest individual reaching 196 mm in November of the year. Among the adult fish examined, the largest female had a body-length of 410 mm, weighing 360 g, 4 years of age; the largest male was 400 mm in body-length, weighing 235 g, and 4 years old too. The minimum sizes of sexually mature individuals were: female 96mm, 6g; male 117mm, 6g; both being one year of age.The ratio between scale-radius and body-length for different age groups is nearly constant.The span of life of this anchovy is 4 to 5 years in general. No individuals upward of 6 years of age ever occurred in our collections, which contained over 4000 specimens intended for age-determination.