The surgical operation system includes: a treatment section for treating a living tissue of a treatment target； an ultrasound generation section for providing ultrasound to the treatment section； an ultrasound drive power supply section for supplying ultrasound drive power to generate ultrasound to the ultrasound generation section； a high-frequency power supply section for supplying high-frequency power to the treatment section； an impedance detection section for detecting an ultrasound impedance of the living tissue and a high-frequency impedance of the living tissue； and a control section for controlling the ultrasound energy amount and the amount of high-frequency power or a crest factor value thereof in response to the detected values of ultrasound impedance and the high-frequency impedance.
