Cancer is a leading cause of death worldwide. In 2018, 9.6 million deaths were attributed to cancer, and it is affecting around 18 million patients each year. Natural products have been considered as the major source of lead compounds for cancer treatment. A large number of natural products have been reported by researchers all over the world and many of them are in clinical trials. In recent years, there has been a growing interest in pentacyclic triterpenoids such as Oleanolic acid, -boswellic acid, ursolic acid, betulinic acid, glycyrrhetinic acid and maslinic acid as potential anticancer agents reflected by the exponential increase in the number of scientific publications and patents published on these natural products all over the world. Moreover, some of these pentacyclic triterpenoids have already been marketed in some countries as therapeutic agents for the treatment of several disorders such as cancer, diabetes, inflammation, liver disorders, etc. Two major derivatives of oleanolic acid, CDDO and CDDO-Me, have been entered into clinical trials against cancer. This book highlights the potential of oleanolic acid and its derivatives in the treatment of several human disorders. Initial chapters discuss the sources, extraction, biosynthesis and various reported biological activities of oleanolic acid while subsequent chapters describe the in vitro and in vivo applications of oleanolic acid and its different derivatives in several diseases such as bacterial infections, breast cancer, colon cancer and hepatic disorders. The last chapter of the book describes the nanoparticle-mediated delivery of oleanolic acid in cancer.