World of Zoo will simulate a zoo, and players will care for 95 different species of animals, from 11 different families, and place it in one of the 20 exhibits. The goal of the game is to keep the animals in the zoo happy, ways to do this include: feeding the animals, playing with the animals, and improving the animals exhibits. Keeping the animals happy will result in hearts and tokens for the player, who can then redeem their hearts and tokens for food, tools, and new animals.
Certain achievements can earn the player certain objects, for example: new species can be unlocked, or in-game awards earned. One example of an in-game award is the player raising in status with one animal family, for the big cat family, awards range from, lowest to highest, "Junior Big Cat Handler" to "Big Cat Whisperer".
If the player scares the animals too much, they can attack.
The game will also feature an "Animal Creator", a feature that allows players to create and customize animals' personalities and appearances similar to Spore; along with an "Animal Adoption Network" feature—another way players can add animals.
Every animal has unique personalities and behaviors; the player's goal is to earn trust and happiness of each animal, so the player must find a method to gain trust and happiness from each animal. Trust the animal has in the player is measured via a trust meter; after the trust meter gets to rank six, the player can hypnotize animals.
The Wii version of the game can function as single player; but also can also support multiplayer mode up to four players. The Wii Remote is used to control the game in both modes; in multiplayer, player one controls the camera.
The PC version includes six animal groups (big cats, giraffes, horses, koalas, pandas, and small monkeys), while the Wii version adds an additional five groups (antelope, bears, crocodiles, elephants, and penguins). The DS version has the same amount of animal groups as the Wii version, but with several differences. The antelope and horse groups are shrunk and merged into a "hoofed animals" group (which adds the okapi), the addition of a canids group (which includes the spotted hyena), and generally fewer animals.