To evaluate the long-term trends in the germplasm resources of Euchiloglanis kishinouyei in the Jinsha River Basin， the age composition and growth characteristics of 208 samples collected from the basin in 2004 were preliminarily analyzed， and then compared with the population data from the same water body in later periods. The results showed that： （1） The samples’ body length ranged from 114 to 286 mm， and body weight ranged from 25.0 to 470.0 g； 115 fish ages were identified， ranging from 4 to 14 instars， primarily between 8 and 11 instars. The relationships between body length （L） and body weight （W） was W = 3×10^-5L^2.8838 （R²=0.918 8， n=208）， indicating a consistent growth pattern. The body length and body weight growth were modeled using the von Bertalanffy growth equation were as follows： L_t = 248.3［1-e^{-0.089（t+2.495）}］， W_t = 242.0［1-e^{-0.089（t+2.495）}］^2.8838. The inflection point age was 9.38 years， with corresponding body length and body weight of L_i = 162.2 mm and W_i = 70.9 g， respectively， indicating slow growth of E. kishinouyei in the Jinsha River Basin. （2） Compared with the data from the late stage of the same water population， the maximum body length， maximum body weight， and maximum age of the E. kishinouyei in this study are greater， with a higher proportion of large and older individuals. The value of b in the body length-body weight relationship was higher， indicating an isometric growth pattern， which differs significantly from the allometric pattern observed previously （b=2.459 6<3） for E. kishinouyei in the same water area during 2018-2019. The inflection point age is delayed， and the proportion of individuals beyond this age is higher. Additionally， the asymptotic length L_∞， asymptotic weight W_∞ and apparent growth index φ were all larger. It is showed that the populations of E. kishinouyei exhibit a significant trend of reduced age and miniaturization over time. Relevant conservation efforts should be implemented as soon as possible to protect the important germplasm resources of E. kishinouyei in the Jinsha River Basin.