An ejector apparatus wherein, in mounting a lift core to a slide base, and in mounting an ejector core to an ejector plate, it is easy to mount the lift and ejector cores to the slide base and the ejector plate, and simultaneously perform adjustment that allows for thermal expansion of the cores. The ejector apparatus includes a lift core extending through a core constituting a mold and movably installed in a longitudinal direction of the lift core with respect to a surface of the core; an ejector plate arranged between the core and a base plate, and being capable of moving up and down, the base plate being arranged below and spaced from the core; and an adjustment coupling constructed such that a lower end portion of the lift core is supported to expand and contract in a longitudinal direction of the lift core relative to the ejector plate.