This manuscript is intended for textile engineering students at the National Engineering School of Monastir. It focuses on the physico-chemical properties of protein-based textile materials.The text is clear and concise, and illustrated with numerous didactic diagrams. The theoretical bases are presented in a logical and progressive manner throughout the chapters.The book is divided into four chapters. The first chapter introduces wool fibers. The second chapter examines the production and properties of silk fibers. The third chapter deals with other protein fibers of animal origin. The final chapter looks at methods for identifying protein fibers and their care. At the end of the manuscript, the reader will be able to evaluate his or her knowledge by answering the various application exercise questions.