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Insulin-like growth factors (IGFs) play central roles in the growth and development of vertebrates. Blotched snakehead (<i>Channa maculata</i>), an economically significant fish, exhibits obvious sexual dimorphism and achieves sexual maturity in one year. However, the role of IGFs in <i>C. maculata</i> remains unknown. Three <i>IGF</i> genes were identified in <i>C. maculata</i>, designated as <i>CmIGF1-1</i>, <i>CmIGF1-2</i>, and <i>CmIGF2</i>. The cDNA sequences of these genes are 1184, 655, and 695 bp, encoding putative proteins of 168, 131, and 215 amino acids, respectively, and all three proteins contain a conserved IGF domain. Quantitative real-time PCR (qPCR) revealed the predominant expression of <i>CmIGFs</i> in the liver of adult fish, with higher expression levels observed in males. Notably, <i>CmIGF1-1</i>, <i>CmIGF1-2</i>, and <i>CmIGF2</i> displayed analogous expression profiles in the liver across various developmental stages, peaking at 365 days after hatching (dah). Subsequently, 600 individuals at 75 dah, at an early developmental stage, were randomly divided equally into six groups and reared in aerated 2 m × 2 m × 2 m cement ponds at 26.0 ± 1.0 °C. Following a one-week acclimatization period, fish without observed abnormalities were intraperitoneally injected with either 17α-ethynylestradiol (EE₂) or 17α-methyltestosterone (MT) at a dose of 10 μg/g body weight. Three groups underwent short-term hormone treatment, and the remaining three groups underwent long-term hormone treatment, which included five injections at two-week intervals over ten weeks. The analysis of <i>CmIGFs</i> expression levels in the liver under different hormone treatments revealed that EE₂ suppressed the expression of <i>CmIGF1-1</i> and <i>CmIGF1-2</i> while promoting <i>CmIGF2</i> expression. In females, MT up-regulated the expression of <i>CmIGF1-1</i> and <i>CmIGF2</i> in a time-dependent manner, but consistently inhibited <i>CmIGF2</i> expression. In males, MT promoted the expression of <i>CmIGFs</i> in a time-dependent manner, reaching peak levels for <i>CmIGF1-1</i>, <i>CmIGF1-2</i>, and <i>CmIGF2</i> after 8, 10, and 2 weeks of injection, respectively. Additionally, <i>CmIGF1</i> and <i>CmIGF2</i> might exhibit a complementary relationship, with a compensatory increase in <i>CmIGF2</i> expression in response to low <i>CmIGF1</i> concentration. These findings highlight the potential key role of IGFs upon growth and their regulation by sex steroid hormones in <i>C. maculata</i>, providing a crucial foundation for future research aimed at elucidating the molecular mechanisms underlying the growth dimorphism between female and male blotched snakeheads.