PURPOSE: To obtain a body warmer that can be used in a flat form, by making a bag- like member having one face made of an air permeable sheet and the other face made of a hygroscopic sheet, forming many small chambers by sealing the bag-like member into a checkered pattern, and filled these chambers with a mixture consisting mainly of iron powder and a metal oxide such that they are mixed uniformly in these chambers.

CONSTITUTION: A body warmer A of this invention, particularly suited for use with a poultice 7 and applied to an affected part of a human body, includes a bag-like member 4 which is obtained by superposing an air-permeable sheet 1, for instance, made of a synthetic resin or a fibrous material having air permeability and water repellency on a hygroscopic sheet 2 obtained, for instance, by laminating a porous sheet of a synthetic resin on a hygroscopic, nonwoven fabric, and forming many small chambers 3 by sealing the sheet surface into a checkered pattern. Then, a mixture 5 consisting mainly of iron powder and a metal oxide is charged into the small chambers 3. Further, an adhesive layer 6 is formed around the marginal portion of the sheet 2 to have a predetermined width. In use of the body warmer A thus obtained, it is applied to an affected part of the human body by the aid of the adhesive layer 6.