A material to be dried is frozen and is efficiently freeze-dried in a short time, thereby increasing production efficiency. A freeze-drying apparatus includes a vertical tube (2) having an inner circumferential surface formed with a frozen surface (2a), a liquid-supply device (5) for supplying a liquid material to be dried (47) onto the frozen surface (2a), a freezing device (10) arranged around the vertical tube (2) and intended for cooling the frozen surface (2a), a pressure-reduction device (12) which puts an interior area of the vertical tube (2) into a state of vacuum, and an internal heating device (41) in the vertical tube (2). The internal heating device (41) is arranged in the vertical tube (2) along a center axis thereof, and has an outer surface formed with a vertically long circular-cylindrical radiation surface (43). The liquid material to be dried (47) supplied from the liquid-supply device (5) is sprinkled onto the frozen surface (2a), and the frozen surface (2a) is cooled to freeze the dried material (47) into a shape of a pipe. Then, the interior area of the vertical tube (2) is pressure-reduced to supply radiation heat from the internal heating device (41) to the dried material (47) for freeze-drying the dried material (47).