This book provides a comprehensive review of the silkworm as a biofactory for the mass production of various proteins, shedding new light on its potential beyond traditional silk production. Through this book, readers will learn about the silkworm's journey from a domesticated insect to a pivotal player in biotechnology, capable of producing biologically functional proteins due to its ability to undergo post-translational modifications. The chapters cover topics such as the historical significance of silkworms, the impact of baculovirus on biotechnology, and the development of gene expression systems. Readers will discover the intricacies of transient and transgenic expression systems, as well as the challenges of improving protein yield in silkworms. The book also explores the expression of virus-like particles (VLPs) in silkworms and their efficient purification, highlighting their potential as vaccine candidates due to their antigen-displaying capabilities. Particular attention is given to the industrial applications of the silkworm biofactory, discussing the commercialization of expressed proteins and the regulatory hurdles that must be overcome. The author, an experienced practitioner in the field, provides expert analysis and insights into the future of silkworm biofactory and their role in pharmaceutical applications. This book is an invaluable resource for researchers, scholars, and professionals in biotechnology, molecular biology, and pharmaceutical sciences. It offers a unique perspective on the intersection of traditional sericulture and modern biotechnology, making it a must-read for anyone interested in the future of protein expression technology. Whether you are a scientist, academic, or industry professional, this book provides the knowledge and insights needed to understand and harness the potential of the silkworm bioreactor.