An optical fiber manufacturing apparatus includes: a cylindrical shield pipe that is provided above a drawing furnace, and forms a space continuous with the heating space in a vertical direction; a sending rod that has a lower end attached to an optical fiber preform and a lower portion disposed inside the shield pipe, and is configured to insert the optical fiber preform into a heating space of the drawing furnace in the vertical direction; an alignment mechanism that is configured to move the sending rod in a horizontal direction; an inner sealing body that is attached to the lower portion of the sending rod; and an outer sealing body that is mounted on the inner sealing body, is configured to move in the horizontal direction with respect to the inner sealing body, and is spaced apart from the sending rod.