Electrotherapy/ultrasound combination system, with two independent outputs to supply low-and meadium-frequency current for electrotherapy and one ultrasound output at a frequency of 1 and 3 MHz and with continuous or pulsed duty cycles. It is provided with a self-calibrating, double frequency handpiece with a 5cm2 sound head, watertight for use in underwater therapy. In ultrasound therapy, a sensor allows the energy to be supplied only when there is a contact with the patient, sending the operator a visual and auditory feedback. In electrotherapy, instaed, the microcontrollers to the power boards verify in real time that the selected current is deliver corrency and report any possible anomalies.