A freeze-drying method by a far infrared heater including the steps of: mounting the frozen objects to be dried prior to heating in the containers in which an absorption power of the radiant heat from the far infrared heater and a thermal conductivity are high, respectively; mounting the said objects which are contained in the containers into the reduced pressure tank under an atmospheric pressure; heating the containers by the radiant heat from the far infrared heater disposed in the reduced pressure tank; and sublimating the frozen water contents of the objects in a reduced pressure state where sublimation of the objects occurs in the reduced pressure tank.