A door suspension apparatus (1, 3) that supports a door provided in a structure and driven to be opened and closed by an open-close drive mechanism, in a state in which the door is suspended to the structure so as to be slidably moved, and that is connected to the open-close drive mechanism, the apparatus comprising: a drive connection portion that is provided with one of a locking portion and a locked portion of a locking device for locking the door to the structure in a fully closed position through locking between the locking portion and the locked portion, and that is connected to the open-close drive mechanism; a door roller portion that includes a door roller traveling on a rail fixed in the structure, that is connected to the door, and that supports the door in a state in which the door is suspended to the rail so as to be slidably moved; and a variable connection portion (23, 50) that connects the drive connection portion to the door roller portion such that a relative position between the drive connection portion and the door roller portion in a direction along a lengthwise direction of the rail can be changed wherein the door roller portion comprises a first hole portion (32a, 52) that is formed therethrough so as to extend along the lengthwise direction of the rail, the drive connection portion comprises a second hole portion that extends along the lengthwise direction of the rail and that is formed therethrough so as to face the first hole portion (32a, 52), and the variable connection portion (23, 50) comprises a fastening mechanism that includes a member passing through the first hole portion (32a, 52) and the second hole portion and that is capable of fixing the door roller portion and the drive connection portion to each other such that a relative position therebetween can be changed. a drive connection portion that is provided with one of a locking portion and a locked portion of a locking device for locking the door to the structure in a fully closed position through locking between the locking portion and the locked portion, and that is connected to the open-close drive mechanism; a door roller portion that includes a door roller traveling on a rail fixed in the structure, that is connected to the door, and that supports the door in a state in which the door is suspended to the rail so as to be slidably moved; and a variable connection portion (23, 50) that connects the drive connection portion to the door roller portion such that a relative position between the drive connection portion and the door roller portion in a direction along a lengthwise direction of the rail can be changed wherein the door roller portion comprises a first hole portion (32a, 52) that is formed therethrough so as to extend along the lengthwise direction of the rail, the drive connection portion comprises a second hole portion that extends along the lengthwise direction of the rail and that is formed therethrough so as to face the first hole portion (32a, 52), and the variable connection portion (23, 50) comprises a fastening mechanism that includes a member passing through the first hole portion (32a, 52) and the second hole portion and that is capable of fixing the door roller portion and the drive connection portion to each other such that a relative position therebetween can be changed.