To investigate the current structural status of the Feiyun River Estuary ecosystem under the influence of factors such as fish stock decline and eutrophication， and to evaluate the proliferation capacity of the water-purifying fish species Konosirus punctatus in this area， this study analyzed ecosystem characteristics using the Ecopath model based on biological resource survey data collected from four voyages in the Feiyun River Estuary between 2022 and 2023. The study also estimated the proliferation capacity of Konosirus punctatus by considering food web structure and energy flow. The model's functional groups encompassed 26 categories， essentially covering the entire process of energy flow within the ecosystem. The results revealed： （1） The trophic levels in the Feiyun River Estuary ranged from 1.00 to 3.84， with a total conversion efficiency of 8.623%. （2） The ratio of total primary production （TPP） to total respiration （TR） in the ecosystem was 1.629， which is greater than 1； the connectance index （CI） was 0.413， which is less than 1； and the system omnivory index （SOI） was 0.234， also less than 1. （3） The existing biomass of Konosirus punctatus was 0.040 5 t/km²， with a proliferation ecological capacity of 0.081 0 t/km². After proliferation， the TPP/TR， CI， and SOI values of the ecosystem all approached 1 more closely. The research indicated that： （1） The energy flow in the Feiyun River Estuary ecosystem generally adhered to the laws of the energy pyramid， with a food web structure dominated by grazing food chains. （2） The ecosystem's maturity was relatively low， its food web structure was simple， its resistance to external disturbances was weak， and its energy utilization efficiency was insufficient. （3） Scientific stock enhancement and release of Konosirus punctatus could promote the maturity and stability of the Feiyun River Estuary ecosystem. This study provides valuable insights for the conservation of fishery resources and ecological environment protection in the Feiyun River Estuary.