To provide a tooth brush which can indicate a standard brushing time to enable the proper brushing.

A brush handle 1 is formed of a material which is discolored by sensing the temperature. When the tooth brush A is used in brushing the mouth, the temperature of the tooth brush A approaches the temperature in the mouth depending on the time of use. By setting the sensing temperature by the relationship between the temperature of the brush handle 1 and the time of use, the time of use can be known by the discoloration of the brush handle 1. The appropriate brushing time can thus be indicated.