To provide a method of manufacturing a freeze-cast substrate which minimizes a distorted volume of the substrate.

One of methods of manufacturing the freeze-cast substrate 34 includes a process in which slurry 30 is put into a forming unit 10 having a mold 12 in a casting vessel 14 and a process in which the slurry 30 is frozen in order to minimize strain in the substrate 34 while controlling a temperature gradient in the forming unit 10 and a temperature of the slurry 30 is reduced in order to form the substrate 34. Another manufacturing method includes the process in which the slurry 30 is put into the forming unit 10 having the mold 12 in the casting vessel 14, a process in which heat insulating material 40 is installed around at least a part of the casting vessel 14 in order to minimize strain in the substance 34 by minimizing the temperature gradient in the forming unit 10 and a process in which the temperature of the slurry 30 is reduced in order to freeze the slurry 30 and form the substance 34.