<p>Sericulture is the practice of rearing silkworms on specific host plants for the production of natural silk. It has been carried out since ancient times. Among the various silkworms, the fully domesticated mulberry (<i>Bombyx mori</i>), the semi-domesticated Eri (<i>Samia ricini</i>) and the wild species or vanya silkworms- Muga (<i>Antheraea assamensis</i>) and Tasar (<i>Antheraea mylitta</i>) represent the major sources of commercial silk in India. Each species has distinct physiological and anatomical features that determine its feeding behaviour, silk production and adaptability to environmental conditions. Although their ecology, host plants, silk characteristics and rearing practices differ among these species, the internal anatomy of these silkworms follows a conserved lepidopteran pattern. In the present study, comparative analysis of internal organs and other external structures of all four different silkworm species were examined using a stereo zoom microscope. The major internal organ includes a digestive tract, tracheal system, circulatory system, nervous system, excretory system, silk gland and reproduction system. Observations revealed species-specific differences in tracheal coloration, silk gland development, fat-body texture and reproductive morphology, influenced by their ecological adaptation and host-plant specialization. External features such as true legs, pseudo-legs, spiracles, eyes and antennal structures of adult moths are also documented to provide integrated anatomical profiles. Such comparative analyses have helped to elucidate functional adaptations concerning feeding habits, cocoon formation, spinning behaviour and environmental tolerance.</p>