This diploma thesis studies tree diversity in cocoa agroforestry systems in Huayhuantillo village in Peruvian Amazon. Cocoa trees and shade trees have been measured within 15 study plots in agroforestry plantations in Huayhuantillo, Peru. Shade tree species were identified and tree diversity in cocoa plantation was evaluated. Within 15 study plots have been observed 195 individual trees belonging to 24 tree species both native and exotic to Amazon. Consequently results of tree diversity in Huayhuantillo cocoa agroforestry plantation were compared with tree diversity of forests from similar natural conditions in Peruvian Amazon and with European agroforestry system. Comparison of species diversity based on measurements has proved higher species diversity in forest reserve. Benefits of agroforestry systems for tree diversity conservation were also evaluated and compared with European agroforestry systems.