A treatment system includes a holding section that has a heat generation section, a signal output section that supplies a drive signal to the heat generation section, a setting section that sets a target temperature of the heat generation section, a signal detection section that detects the drive signal, a signal extraction section that extracts an extracted signal of a predetermined frequency band from the drive signal detected by the signal detection section, a fault detection section that detects a precursory phenomenon of a fault of the heat generation section when the extracted signal reaches a predetermined threshold, and a control section that controls the drive signal to the heat generation section in a treatment mode for treating the living tissue at the target temperature or in a test mode for detecting the precursory phenomenon.