<p>Disclosed is an atomic layer deposition apparatus for forming a thin film on a substrate, which comprises: a first container for forming a first inner space; a second container which is a cylindrical container that is arranged within the first container and forms a second inner space, and has a first opening at one end of the cylinder, through which a starting material gas for forming a thin film on the substrate flows toward the second inner space; and a pressing member which comprises a gas supply port for supplying the starting material gas into the second inner space through the first opening, and separates the second inner space from the first inner space by pressing the second container in the longitudinal direction of the cylindrical second container.</p>
