A vacuum heat insulator has a core formed of a glass fiber laminated body where glass fibers are laminated in the thickness direction, and an enveloping member that covers the core and has gas barrier property. The inside of the enveloping member is evacuated and the enveloping member is sealed. The core is pressurized and molded and the glass fibers are drawn by heat deformation of the glass fibers at a temperature at which the glass fibers start to slightly deform due to own weight of the glass fibers or a temperature at which the glass fibers become deformable due to a vertical load in pressing and the sectional shapes of the glass fibers do not significantly vary. Additionally, the shape of the core is kept by entanglement of parts of the glass fibers instead of binding of the glass fibers.