Insect antimicrobial peptides (AMPs) are crucial components of the innate immune system in insects, offering broad-spectrum antimicrobial activity and potential applications in medicine, agriculture, and food safety. This review summarizes the discovery, classification, structure, and mechanisms of action of AMPs in various model insects. AMPs are categorized into four main groups based on their secondary structures: α-helical, β-sheet cysteine-rich, proline-rich, and glycine-rich AMPs. Each group exhibits distinct antimicrobial activities and is involved in different immune responses. The review also discusses the evolutionary relationships of AMPs across insect species, highlighting their conservation and diversity. AMPs are regulated by multiple signaling pathways, including the Toll, IMD, and JAK-STAT pathways, as well as additional pathways involving nitric oxide, insulin-like signaling, and hormones. These pathways are essential for the production and regulation of AMPs in response to microbial threats. The review also explores the potential applications of insect AMPs in various fields, including food preservation, agriculture, and pharmaceuticals. Despite their promising applications, challenges remain in the widespread use of AMPs due to factors such as proteolytic instability, potential hemolysis, and high production costs. The study provides a comprehensive overview of AMPs in insects, offering insights into their roles in immunity and potential uses in various industries.Insect antimicrobial peptides (AMPs) are crucial components of the innate immune system in insects, offering broad-spectrum antimicrobial activity and potential applications in medicine, agriculture, and food safety. This review summarizes the discovery, classification, structure, and mechanisms of action of AMPs in various model insects. AMPs are categorized into four main groups based on their secondary structures: α-helical, β-sheet cysteine-rich, proline-rich, and glycine-rich AMPs. Each group exhibits distinct antimicrobial activities and is involved in different immune responses. The review also discusses the evolutionary relationships of AMPs across insect species, highlighting their conservation and diversity. AMPs are regulated by multiple signaling pathways, including the Toll, IMD, and JAK-STAT pathways, as well as additional pathways involving nitric oxide, insulin-like signaling, and hormones. These pathways are essential for the production and regulation of AMPs in response to microbial threats. The review also explores the potential applications of insect AMPs in various fields, including food preservation, agriculture, and pharmaceuticals. Despite their promising applications, challenges remain in the widespread use of AMPs due to factors such as proteolytic instability, potential hemolysis, and high production costs. The study provides a comprehensive overview of AMPs in insects, offering insights into their roles in immunity and potential uses in various industries.