The book titled “Comprehensive Book on Entomology” is a compilation that provides a thorough treatment of the subject of Entomology, covering the revised syllabi for Agricultural Research Service (ARS) competitive examinations. This book encompasses both the fundamental and applied aspects of Entomology, enriched with the latest advancements in the field. It holds immense significance for Ph.D. students who are exclusively preparing for Agricultural Research Service (ARS) exams. The book is divided into three parts. Part I comprises the first six chapters, which delve into topics such as Systematics, Morphology, Embryology, internal anatomy and physiology, Ecology, Biological control and Chemical control and toxicology. Part II encompasses the following six chapters such as Host plant resistance, Innovative approaches in pest control, Integrated pest management, Pesticides application equipments, Pests of field crops and their management and Pests of horticultural crops and their management. Part III includes the remaining chapters, which cover topics such as Pests of stored product and their management, Arthropod vectors of plant diseases, Honey bees and beekeeping, Silkworms and sericulture, Lac insect and Other useful insects. The book has been meticulously crafted, presenting a comprehensive and lucid compilation of information to facilitate easy reading and understanding.