Initially, in 1949, the construction of a zoo in the vicinity of Železná studnička was considered. However, the expertise confirmed this location as inappropriate. A new alternative was adopted - to build a zoo in Mlynská dolina, originally on an area of about 9 ha, with the prospect of expanding the area to 90 ha. Initially, the construction of a zoo at PKO was considered, but later, due to the importance of Bratislava as the capital of Slovakia, the construction of an independent breeding and educational facility was started.
Construction began in 1959 and the grand opening of the ZOO took place on May 9, 1960 . In the first decade of the existence of the Bratislava ZOO, the first breeding successes came (breeding macaques, baboons, porcupines, nutria, leopards, puma and dings). As one of the first zoos in Europe, we bred young lynx. Artificial breeding of antelopes, baboons, fallow deer and roe deer deserve special attention. Among the educational activities, the advisory service for small animal breeders and hobby groups - equestrian, falconry, zoological, breeding and nature conservation club - was very successful. Later, the collection of animals was supplemented by many rare species of animals and the Bratislava ZOO achieved the most significant breeding success with the first artificial breeding of spotted leopards and grazing hyenas in the former Czechoslovakia.