To provide an assisting tool for hair coloring/bleaching not making finishing uneven and capable of coloring/bleaching the hair to the root at the time of hair coloring/bleaching.

The assisting tool for hair coloring/bleaching has a structure capable of bringing an arch comb 1 into close contact with the head part by combining the comb 1 provided with recesses 4 for the ears on both ends with a rubber string 3. The comb 1 is introduced from the lower side of the hair and made to move little by little at regular intervals from the lower part of the neck to the top part of the head. Drawing pieces of the hair along the lower side of the comb 1 each time makes a small amount of the hair appear, allowing the hair to be colored or bleached from the root. Allowing the pieces of the hair to be finely divided in a horizontally linear shape by the comb 1 makes the hair evenly finished.