A method of making a plate-like frozen raw hamburger-like matter includes: a filling step for filling a constitutional material of the raw hamburger-like matter between a first thermal seal a second thermal seal, provided in a direction perpendicular to the conveying direction; a deaerating step of pressing the film so that the filled constitutional material is extended until the second thermal seal is provided; a forming step for forming the plate-like raw hamburger-like matter by equalizing the constitutional matter, therein; and a freezing step for maintaining its shape by rapidly freezing the package bag enclosing the raw hamburger-like matter.