in the Guishi reservoir Guangxi Province using scales, opercula, and anal-fin spines. We collected 688 specimens between September 2008 to August 2009. The interpretation of age based on scale readings was reliable. Annual rings were formed primarily by the pattern of sparseness-denseness and the cut of the scales. The pattern of sparseness-denseness was visible in the prezone region whereas the cut pattern was present on the rear-side region. Annuli formation took place primarily between April and June each year, likely related to the timing of reproduction. The estimated ages ranged between 0 and 4 years old, but were dominated by the younger age classes (age 0 and 1). The body-length of specimens ranged from 11.25 to 40.50 cm, with the majority (70.49%) being 15–21 cm. Body weight ranged from 29.1 to 2 257.8 g, but most fish (62.12%) were between 100–300 g. The body length-scale radius relationship was 9, =623) therefore, was considered to be isometric. The growth equations for body length and weight were 3.087 6, respectively. The inflexion age on the growth rate curve for weight was 3.93, and corresponded to a body-length of 39.89 cm and weight of 1 554.81g. Our data suggest thatpopulation had been overexploited. To protect the population and allow for sustainable utilization, we suggest only fish greater than 990 g (age 3) should be harvested.