The present invention provides a flexible wire grid polarizer used in a visible ray band and a fabricating method thereof. The present invention includes the steps of forming a non-adhesive layer on an inner area of a lower substrate, forming a flexible polymer substrate on the lower substrate including the non-adhesive layer, forming a thin metal layer on the flexible polymer substrate, forming a metal grid pattern by etching the thin metal layer, dicing a wafer staying within a boundary of the non-adhesive layer on the lower substrate, and separating the lower substrate including the non-adhesive layer from the diced wafer to complete the flexible wire grid polarizer.