Abstract: The anchovy (Engraulis japonicus) is a key species in the Yellow Sea and East China Sea ecosystems, playing a vital role in energy flow and fishery resources. Since its severe collapse in the late 1990s under intense fishing pressure, the population has shown slow growth, and its resource sustainability remains a major concern despite recent signs of increase. This review aims to systematically elucidate the multidimensional mechanisms constraining the effective recruitment of the Yellow Sea anchovy population, thereby providing a scientific basis for sustainable resource management. By integrating findings from stock assessment, early life history biology, ecophysiology, population genetics, and climate change research, this paper identifies and analyzes key constraints on E. japonicus recruitment from the perspectives of spawning stock biomass, reproductive traits, critical bottlenecks during early development, genetic structure, and environmental stressors. The E. japonicus biomass in the Yellow Sea plummeted from 4.10 million tons in 1993 to a low of 0.11 million tons in 2003. More than two decades later, the current population size remains far below historical levels. Key mechanisms constraining effective recruitment include: ① Severe depletion of spawners and eggs: In May 2010, E. japonicus egg abundance in the Yellow Sea was only 6.01% of that in May 1986, and dropped to 0.05% in the same comparable area. ② Decreased egg quality: Natural mortality rates of eggs in major spawning grounds increased from 64.10% during the initial exploitation phase to 80%-91% post-collapse, accompanied by a general trend towards smaller egg size. ③ Small mouth size of first-feeding larvae: At 3.7 mm total length, larval mouth size is only about 250 μm, significantly smaller than most marine fish species. ④ Short PNR window: Under 23.0-24.8°C, the mixed feeding stage lasts only one day, with the Point of No Return (PNR) occurring at 6 days post-hatching. ⑤ Low swimming capacity: Cruising speeds of northern anchovy (E. mordax) larvae are only 0.3-0.5 cm/s, much lower than those of clupeids. ⑥ Climate warming stress: Rising sea temperatures lead to smaller egg size, shorten the mixed feeding stage, and may shift conditions away from the optimal growth temperature window of 21-22°C for larvae and juveniles. ⑦ Genetic constraints: The population exhibits a pattern of high haplotype diversity but low nucleotide diversity with strong gene flow, suggesting potential cryptic erosion of genetic diversity under high fishing pressure, which may undermine its evolutionary potential. E. japonicus recruitment in the Yellow Sea is jointly constrained by insufficient spawning stock biomass, multiple vulnerabilities in early life history, potential genetic structure limitations, and superimposed climate stressors, posing multiple bottlenecks to resource sustainability. This study reveals the multidimensional constraints on the recruitment dynamics of small pelagic fish and provides important theoretical insights for developing ecosystem-based fishery management strategies.