Small yellow croaker (Larimichthys polyactis) plays an important role in marine fisheries in China. However, information on the population dynamics and exploitation patterns of L. polyactis is required to enable its sustainable management. The present study aimed to generate essential biological parameters that affect the growth, mortality, and stock status of L. polyactis using length-frequency data collected from the Southern Yellow Sea in 2018. The total mortality coefficient (Z) was derived from the length-converted catch curve. Further, biological reference points were predicted from yield- and biomass-per-recruit analyses. The exploitation patterns of L. polyactis were also evaluated using size-based indicators. The following growth parameters of the von Bertalanffy growth equation were estimated: BL_∞=29.26 cm, K=0.26/a, and t₀=?0.6326 a. The total mortality (Z), natural mortality (M), and fishing mortality (F) rates were 2.83, 0.52, and 2.31 per year, respectively. The current fishery exploitation rate (E=0.82) was higher than the estimated biological reference points (E_max=0.57), confirming the over-exploitation of L. polyactis in the Southern Yellow Sea. Size indicators of the catches further revealed that 45.18% of the catches were harvested before sexual maturity was achieved, with mega-spawners comprising only 0.47%. This finding indicates that the stock suffered both from growth overfishing and recruitment overfishing. Based on the Logistic selection model, the estimated total length with a 50% probability of capture was 13.75 cm. For the effective and sustainable management of fisheries, fish size at first capture (L_c) must be increased to achieve the optimal capture total length (L_opt=19.2 cm).