An atomic layer deposition apparatus for forming a thin film on a substrate, including a first container that defines a first inner space, a second container provided inside the first container to define a second inner space, the second container being canister-shaped and including a first opening at one end thereof, a source gas that forms the thin film on the substrate flowing to the second inner space through the first opening, and a pressing member including a gas supply port for supplying the source gas to the second inner space through the first opening, the pressing member being configured to press the second container in a longitudinal direction of the second container so that the second inner space be separated from the first inner space.