Insect pests are causing a serious economic damage to important crops worldwide. However, insect pest control has made a major contribution to integrated pest management (IPM) in the world. This text book is designed to enhance the Introduction of Agricultural Entomology by presenting the core material in a simple way. The text covers the major conceptual themes in agricultural entomology such as Economic importance of insect pests, morphological structures and function, growth and development, ecology and behaviour, feeding habits, beneficial insects, social insects, post-harvest grain losses, Major insect pests of cotton and rose, insect pest management and practical application. The preparation of this text took about two and half years to complete. My motivation for preparing this text is to help Agricultural teachers, undergraduate students, development workers, non-governmental organization experts and junior researchers willing to promote entomological practices and theoretical application. So I hope the text will prove useful to all those interested in promoting agricultural entomology in formal and informal application in developing countries in general.