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2010年10月至2011年7月在长江上游宜宾至江津江段，采集异鳔鳅（ Xenophysogobio boulengeri）405尾。采用体长股分析法（ LCA）对其资源量进行初步评估，运用Beverton-Holt动态综合模型对其资源变化趋势进行分析。结果显示：现阶段长江上游异鳔鳅的补充年龄（tr）、开捕年龄（tc）及极限年龄（Tmax）分别为1.1a、1.5a及11.7a；种群总死亡系数（Z）、自然死亡系数（M）及捕捞死亡系数（F）分别为1.31/a、0.57/a及0.74/a。当前开发率（Ecur）为0.57，表明该种群已面临较高的捕捞压力。2010年至2011年长江上游异鳔鳅的年平均资源量及资源尾数分别为0.350×104 kg、0.533×106尾，初始资源量及资源尾数分别为0.627×104 kg、0.957×106尾。研究表明：长江上游异鳔鳅种群资源已处于过度利用状态，且渔获物以幼鱼为主。建议将长江上游异鳔鳅的最小可捕规格定为94.43 mm，以保护其资源不被过度开发。“,”Based on the fishery resources monitoring data collected in the Yi Bin and Chong Qing section of the upper rea -ches of the Yangtze River from October 2010 to July 2011 , the stock biomass was estimated by length-based cohort analysis ( LCA) , the population dynamics was evaluated by Beverton-Holt dynamic model .The ages at recruitment , at first capture and the terminal age were 1.1a, 1.5a and 11.7a, respectively.The total mortality rate (Z), natural mortality rate (M) and fishing mortality rate (F) of the population were 1.31/a, 0.57/a and 0.74/a, respectively.The current exploitation rate (E) was 0.57, indicating that the population had faced with overfishing .From 2010 to 2011, the average stock bio-mass and number of X.boulengeri in the upper Yangtze River were 0.350 ×104 kg and 0.533 ×106 ind., the initial stock biomass and number were 0.627 ×10 4 kg and 0.957 ×10 6 ind, respectively . It was concluded that the stock of X.boulengeri in the upper Yangtze River had been over-exploited, and the young fish were occurred in the catches with large amount .To protect the resources of X.boulengeri in the upper Yangtze River , the length at first capture should be fixed with 94.43 mm.