The province of Loja is home to a great diversity of forest species such as C. officinalis, which has been subject to exploitation with no forecasts for the future; Its medicinal properties caused the populations of Loja to have an excessive demand for the cascarilla from the XVII century, causing the irrational exploitation of the species that comprise this genus, in the forests of Cajanuma and Uritusinga the cascarilla was exploited until the Second World War, It had a great commercial importance due to quinine, which is the alkaloid extracted from the bark of some of its species and was the only effective remedy against malaria; years later, the synthesis of synthetic chloroquinine displaced quinine in its pharmacological use. This book aims to contribute to the strengthening of the studies of the Cinchona species genus, in the generation of knowledge on the history, biology and plant physiology, to promote the conservation and preservation of the species C. officinalis in degraded ecosystems of the southern region of Ecuador.