To provide a hair material for a toothbrush that has an indicator function capable of confirming whether a mouth cleaning is thoroughly achieved by a hue change of the hair material, a method for producing the same, and a toothbrush.

There is provided a hair material for a toothbrush including cut bristles of a thermoplastic resin monofilament. A thermoplastic resin layer that contains a thermochromic compound a hue of which changes according to a temperature change in an amount of 0.5 to 20 wt.% is formed on a surface of the thermoplastic resin monofilament.