A surgical system, comprising: an ultrasound treatment instrument having an ultrasound transducer; a power supply apparatus to which the ultrasound treatment instrument is detachably connected; an energy supply section that is provided in the power supply apparatus, and supplies drive energy that causes the ultrasound transducer to be ultrasound-driven as output energy; a clock that is provided in the power supply apparatus, and measures a present time; a time updating section that is provided in the power supply apparatus, and outputs the present time; a storage section that is provided in the ultrasound treatment instrument, stores a final updated time as an updated time that is at least finally updated in the present time which is outputted from the time updating section, and stores a number of times of use of the ultrasound treatment instrument; a time period calculation section that calculates a non-connection time period in which the ultrasound treatment instrument and the power supply apparatus are not connected based on a difference between the final updated time which is stored in the storage section, and the present time by the clock; a comparison section that determines whether or not the non-connection time period which is calculated in the time period calculation section exceeds a predetermined time period; a processing section that performs processing of generating an update signal that causes the number of times of use to be updated when a parameter including at least one of a number of output times of the drive energy, an output time period of the drive energy, an output power of the drive energy, an output current integrated value of the drive energy, an output voltage integrated value of the drive energy, an output power integrated value of the drive energy, a continuous output time period of the drive energy, an output time period integrated value of the drive energy, and a connection time period of the ultrasound treatment instrument and the power supply apparatus exceeds a predetermined threshold value, when it is determined in the comparison section that the non-connection time period exceeds the predetermined time period; and a number of times of use updating section that updates the number of times of use based on the update signal. an ultrasound treatment instrument having an ultrasound transducer; a power supply apparatus to which the ultrasound treatment instrument is detachably connected; an energy supply section that is provided in the power supply apparatus, and supplies drive energy that causes the ultrasound transducer to be ultrasound-driven as output energy; a clock that is provided in the power supply apparatus, and measures a present time; a time updating section that is provided in the power supply apparatus, and outputs the present time; a storage section that is provided in the ultrasound treatment instrument, stores a final updated time as an updated time that is at least finally updated in the present time which is outputted from the time updating section, and stores a number of times of use of the ultrasound treatment instrument; a time period calculation section that calculates a non-connection time period in which the ultrasound treatment instrument and the power supply apparatus are not connected based on a difference between the final updated time which is stored in the storage section, and the present time by the clock; a comparison section that determines whether or not the non-connection time period which is calculated in the time period calculation section exceeds a predetermined time period; a processing section that performs processing of generating an update signal that causes the number of times of use to be updated when a parameter including at least one of a number of output times of the drive energy, an output time period of the drive energy, an output power of the drive energy, an output current integrated value of the drive energy, an output voltage integrated value of the drive energy, an output power integrated value of the drive energy, a continuous output time period of the drive energy, an output time period integrated value of the drive energy, and a connection time period of the ultrasound treatment instrument and the power supply apparatus exceeds a predetermined threshold value, when it is determined in the comparison section that the non-connection time period exceeds the predetermined time period; and a number of times of use updating section that updates the number of times of use based on the update signal.