A polarizing element manufacturing method includes (a) forming a plurality of fine metal wires by forming a metal film on a substrate and patterning the metal film, (b) applying, onto a base material, a glass precursor solution for forming a protective layer for protecting the fine metal wires, (c) placing the substrate on the base material so that ends of the fine metal wires are immersed in the glass precursor solution, and (d) forming the protective layer by drying the glass precursor solution, and bonding together the base material and the substrate with the protective layer therebetween.