The internationally renowned zoo with an attached aquarium and invertebrate exhibit is active in preservational breeding of animals that are in danger of becoming extinct.

In addition, in-the-wild conservation efforts and research focussing on animals of Madagascar, Wallacea, and Vietnam are actively promoted and supported via cooperation with Cologne University and local projects, such as in the case of Przewalski's horses.

Carl Hagenbeck's enclosure design also influenced the layout of the zoo, as interpreted by naturalistic looking baboon and polar bear rockwork exhibits built around 1914.

Initially, the zoo's financial track was a successful start, but the World Wars in Germany resulted in phases of stagnation.

World War I and the Great Depression resulted in economic losses and development slowdown, and many animals suffered from a lack of food supply.

Species housed include western lowland gorilla, orangutan, bonobo, pygmy marmoset, king colobus, and lion-tailed macaque.

The free-flight aviary in the exhibit includes palm cockatoo, blue-faced honeyeater, Bali mynah, fairy bluebird, wrinkled hornbill, Black-naped fruit dove, Palawan peacock-pheasant, green peafowl, sailfin lizard, Southern crowned pigeon, and reticulated python.

Other species housed include aardvarks, Rodrigues' flying foxes, hamerkops, hadada ibises, cattle egrets, and grey parrots.