Cinchona (pronounced or ) is a genus of flowering plants in the family Rubiaceae containing at least 23 species of trees and shrubs. All are native to the tropical Andean forests of western South America. A few species are reportedly naturalized in Central America, Jamaica, French Polynesia, Sulawesi, Saint Helena in the South Atlantic, and São Tomé and Príncipe off the coast of tropical Africa, and others have been cultivated in India and Java, where they have formed hybrids.

Cinchona has been historically sought after for its medicinal value, as the bark of several species yields quinine and other alkaloids. These were the only effective treatments against malaria during the height of European colonialism, which made them of great economic and political importance. Trees in the genus are also known as fever trees because of their anti-malarial properties.

The artificial synthesis of quinine in 1944, an increase in resistant forms of malaria, and the emergence of alternate therapies eventually ended large-scale economic interest in cinchona cultivation. Cinchona alkaloids show promise in treating falciparum malaria, which has evolved resistance to synthetic drugs. Cinchona plants continue to be revered for their historical legacy; the national tree of Peru is in the genus Cinchona.