To provide a continuous heat treatment apparatus which effectively, economically, safely and continuously performs heat treatment of a wide variety of materials to be treated from a large lot of the materials to be treated to a small lot of the materials to be treated.

The continuous heat treatment apparatus includes along a moving direction of the material to be treated: a degreasing chamber in which the material to be treated is heated and degreased under vacuum atmosphere; a heating zone in which the degreased material to be treated is heated under vacuum atmosphere; and an oil-quenching chamber in which the heated material to be treated is oil-quenched under vacuum atmosphere. The heating zone is divided into a plurality of heating chambers by openable/closable heat insulating doors along the moving direction of the material to be treated in a space surrounded with heat insulating material in a vacuum vessel, and an independently-controllable heater is fitted to each heating chamber.