Zim's Base, or Zim's House, is the home of Zim and GIR, and later on, Minimoose. When Zim and GIR reached Earth, they found an area between two apartment buildings (located within a cul-de-sac), and, using an Irken device resembling a tablet computer, he created a base founded on what Zim thought was normal Earth housing (since GIR was of minimal help at the time). It is a tall, green house with a purple roof and door (which appears to have come from a men's bathroom. It has a satellite dish on one side of the roof, and the lawn is covered in lawn ornaments, including a flamingo, two puffer fish, and a flag that says "I Love Earth". It also has four large robotic Lawn Gnomes, which serve as the base's first line of defense - though they can easily destroy humans, it has been seen in many episodes that passersby can slip by the with ease. Zim's house is located in a cul-de-sac in a suburban neighborhood of The City, just a block or two away from the Membrane home.

The walls of the house appear to be capable of changing shape on command; in episode Plague of Babies, Zim was able to order the house to create a round window in the rear wall of the house, which subsequently disappeared autonomously after he used it.