[Objectives] To support fish resource protection and ecological restoration, this study investigated the age, growth and reproduction of Pseudogyrinocheilus procheilus based on monthly samples collected in the Chishui River between March 2023 and February 2024. [Methods] Scales were used as material for age determination, and von Bertalanffy growth functions were fitted based on the ages determined from scales and the measured body length data. The Chi-square test is used for further validation of the goodness-of-fit of the equation. [Results] The results indicated that the age of P. procheilus ranged from 1 to 5 years, with a predominance of 2 and 3 years of age (Fig. 1), and a sex ratio of 1︰0.53 (female︰male). The relationship between body length and weight was described by the equations W_♀ = 3.948 × 10^﹣6 L^3.317 for females and W_♂ = 2.137 × 10^﹣5 L^2.989 for males (Fig. 3). The t-test of the allometric growth index (b) was further analyzed, uncovering the b value of females is significantly greater than 3 (P < 0.01), indicating a positive allometric growth pattern. Differently, males exhibited a b value of 2.989, suggesting an isometric growth pattern. The von Bertalanffy functions were L_t♀ = 324.89[1﹣e^{﹣0.139(t+ 2.216)}] for females and L_t♂ = 236.25[1﹣e^{﹣0.239(t+ 1.828)}] for males (Fig. 4). The growth rate and acceleration of body length show no inflection point, with growth rate decreasing with age and the acceleration remaining negative. In contrast, the growth rate and acceleration of body weight exhibited inflection points, with inflection ages (t_i) of 6.41 years for females and 3.40 years for males (Fig. 5). The analysis indicated that the first sexual maturation and age occurred at a length of 170.35 mm and an age of 3.12 years for females, and 155.28 mm and 2.65 years for males (Fig. 6), respectively. Analysis of the gonadal somatic index and ovarian development period indicated that spawning occurred from May to September, peaking in May and June (Fig. 7). Studies on egg diameter frequency distributions (Fig. 9) and histological observations of ovarian development (Fig. 8) revealed that P. procheilus employs a single-batch spawning strategy. The mean absolute fecundity and relative fecundity were 4 496 eggs per female and 31 eggs per gram, respectively, with absolute fecundity positively correlated with body length and binomially correlated with body weight (Fig. 11). [Conclusion] Based on the above conclusions, we believe that fishing has a great impact on fish like P. procheilus, which have low individual fecundity and high growth inflection age. Maintaining a long-term fishing ban is the basic measure for fish protection in the upper reaches of the Chishui River.