PROBLEM TO BE SOLVED: To provide a breast milk sterilizer capable of easily and surely sterilizing breast milk.SOLUTION: There are included: an infant-feeding bottle 1 to put breast milk in a metal holder cylindrical body 2 having a cylindrical wall part 21 to insert the infant-feeding bottle 1 into and a heater 5 provided at the outer peripheral side of the cylindrical wall part 21. The infant-feeding bottle 1 is made of resin and has an elastically deformable outer wall part 15 to be inserted into the cylindrical wall part 21, having a polygonal cross-sectional shape. Each of ridge line-like parts 15e of the outer wall part 15 in a polygonal cross-sectional shape is constituted so as to be pressure-welded to the cylindrical wall part 21.SELECTED DRAWING: Figure 2
