This study analyzed the population structure and growth characteristics of chub mackerel (Scomber ja-ponicas) based on its reproductive stocks samples collected in the central East China Sea from March to April in 2021. This analysis was undertaken using otolith interpretation, growth back-calculation, and growth equation fitting. The results showed that there was no significant difference between male and female individuals in the reproductive stock of Japanese mackerel (F=0.376, P=0.54＞0.05). The age structure of male and female was 1?7 years old and the dominant age group was 1?2 years old, accounting for 73.63% of the population. The number of females was more than that of males at three years old and below. For individuals older than three years old, the number of males and females was essentially the same, although the females were lacking in old age individuals. The relationship between fork length and body weight was: W=0.8837×10^–6FL^3.474. A linear functional relationship was the optimal solution for the relationship between fork length and otolith radius; this relationship was FL=184.09R–112.73. The fork length and age data of four models were used to fit three back-calculation models; von Bertalanffy, Gompertz, and Logistic. Among them, the von Bertalanffy equation of the Dahl-Lea model had the lowest AIC and BIC; as such, this model was selected as the best growth equation. The von Bertalanffy fork length growth equation was FLt=427.18 [1?e^{–0.23(t+2.5)}], and the body weight growth equation was Wt=1187.20× [1?e^{(–0.23(t+2.5)}] ^3.47. Following the second derivation test, the age of the inflection point was 2.91 years old, the corresponding inflexion body weight and fork length were 365.03 g and 304.09 mm respectively. These values may be used as an important references for the formulation of Scomber japonicus catch specifications in future.