An apparatus for manufacturing a display device, includes: a heater which generates heat; a pressing member which contacts a target object of a display device to transfer the heat to the target object; a body connected to each of the heater and the pressing member and through which the heat from the heater is provided to the pressing member; and a first housing cover extended from the body to surround the pressing member and the body in a plan view. Engagement of the first housing cover with the target object defines an internal space of the first housing cover having a temperature, and measurement by the apparatus, of the temperature of the internal space, controls bonding of layers of the target object to each other.