A treatment system includes a control apparatus having respective first and second output sources that supplies respective high-frequency power defined by a first electrical energy and a second electrical energy. The control apparatus includes a processor configured to acquire a first value based on the first electrical energy and a second value based on the second electrical energy. Based on the first value, the processor determines influence given to the second value by the first electrical energy. Based on the influence given to the second value, the processor adjusts an output instruction value to the second output source by the first electrical energy and the second value based on the second electrical energy. The control apparatus is configured to properly calculate a physical quantity relating to the first and second electrical energies even when an electrical noise is generated in a state in which multiple electrical energies are simultaneously supplied.
