Sinibotia reevesae is an endemic fish which lives only in the upper reaches of the Yangtze River. The purpose of this study was to determine age structure and growth characteristics of S. reevesae, and to propose effective measures to protect this species. A total of 573 specimens which were monthly collected from April to November 2010 in Zizhong-Longchang section of the Tuojiang River, a tributary river of the Yangtze River. Method：Standard length and body weight of each specimen were measured. Calculation of increment rate and growth indexes of body length and body weight of S. reevesae by Yin Minchen’s methods (1995). The growth of S. reevesae was fitted by the equation of Von Bertalanffy. Statistic analysis of all data were taken using Microsoft excel 2003 and SPSS 19.0. Results: Lapillus moderate thickness and there were clear rings or annuli on it which was the most accurate structure for age determination(Fig. 1). The standard length of the samples mainly ranged from 80~100 mm, accounting for 67.54% of the total (Fig. 2)；total weight mostly ranged from 8~20 g and accounting for 69.11% of the tota1 (Fig. 3). Age of the fishes was identified to five age classes (2~6 years old) and individuals of 3~4 years old were dominated with frequency of 85.91% (Fig 4). Sex ratio (♀∶♂) was 1∶1.11. There was a linear correlation between standard body length and otolith radius and the regression equation was L=125.25RO﹣11.706(n=362，R2=0.8023，P＜0.01) (Fig 5). The increment rate and growth index were analysised by back-calculated body length and the results showed that significant difference between 2~3 years old and 4~5 years old, among them 2 years old was the highest(Table 1). The relationship between standard length (L，unit mm)and total weight(W，unit g) showed no significant difference between ma1es and females, which could be expressed as: W = 5×10-6L3.2868(n=573，R2 = 0.820 2) (Fig 6). The body length has increased rapidly before 4 years old and the increment rate of body weight was the hightest between 3 and 4 years old(Table 2). The growth of S. reevesae was in a constant speed which can be described with von Bertalanffy equation: Lt = 128.72[1﹣e﹣0.1974(t 1.66)], Wt = 42.95[1﹣e﹣0.1974(t 1.66)]3.286 8. Growth rate and acceleration growth rate equation of body length were dL/dt = 25.413 3 e-0.197 4 (t 1.66) and d2L/dt2 =﹣5.015 8 e﹣0.1974 (t 1.66), respectively. Meanwhile, the growth rate and acceleration growth rate equation of weight were dW/dt = 27.8666 e﹣0.1974 (t 1.66) [1﹣e﹣0.1974 (t 1.66)]2.2868 and d2W/dt2=5.5009 e﹣0.197 4 (t 1.66) [1﹣e﹣0.197 4 (t 1.66)]1.286 8×[3.2868 e﹣0.197 4 (t 1.66)﹣1], respectively. The growth inflexion points was 4.37 years with the corresponding standard body lengths 89.46 mm and body weights of 12.99 g (Fig 7). Our data suggest that the resource of S. reevesae had already been fished properly in Zizhong-Longchang section of the Tuojiang River. However, in order to better protect the resource of S. reevesae, measures such as strict ban to unreasonable catching and exploring the hydropower resources should be enhanced.