a cutting tool with a sensor according to the present invention includes an electrically conductive substrate , an insulation film provided on a surface of the electrically conductive substrate , and a sensor circuit of an electrically conductive film provided on the insulation film . the insulation film includes two consecutive insulation layers . even if the plural insulation layers each have defects such as cracks and pinholes which possibly impair the insulation property of the insulation film , the defects present in the plural layers are unlikely to be continuous . therefore , the insulation film has an improved insulation reliability , thereby ensuring proper function of the sensor circuit in the cutting tool .