Forestry is an essential part of ecosystem conservation. It is a basic industry for sustainable economic development and social services. It is also the main battlefield for building a harmonious relationship between humans and nature. In the 1980s and 1990s, the first and second editions of Forest Insects of China were published to meet the needs for forest pest research, teaching, and better pest control methods and strategies. As an important reference book, it greatly assisted in the protection of forest ecosystems in China. It has been nearly 30 years since the second edition was published. China experienced tremendous scientific and economic development during this period. Significant advances occurred in forest entomology research. It becomes necessary to update the second edition of Chinese Forest Insects and to publish an English edition to allow for easy access of the information by international scholars. In the new edition, the following major changes were made. This book introduces nearly 600 species of insects. Each species includes the scientific name, taxonomic status, economic importance, distribution, hosts, biology and behaviour, and prevention and treatment. This book can be used by researchers, students, government agencies, and pest control professionals.