Lepidoptera, comprising butterflies and moths, are generally perceived as harmless insects; however, growing evidence demonstrates that several species possess potent venoms, particularly during the larval stage. Lepidopteran venoms have evolved primarily as defensive adaptations against predators, parasitoids, and accidental human contact. These venoms are delivered through specialised structures such as urticating setae, spines, and venomous scales, which release bioactive compounds upon contact. Venomous caterpillars, including Lonomia obliqua, Doratifera vulnerans, and Comana monomorpha, can cause a range of effects from localised pain and dermatitis to severe haemostatic disorders. Lepidopteran venoms are biochemically diverse, comprising peptides, proteins, enzymes, and inflammatory mediators, and have evolved independently across multiple lineages. Beyond their medical relevance, these venoms represent promising sources of novel bioactive molecules with potential applications in agriculture, medicine, and biotechnology.