BACKGROUND:With the development of medical instruments, more and more traditional surgical operations are replaced by minimal y invasive surgeries. In minimal y invasive surgery, cutting and sealing tissue is a conventional procedure;however, due to the limitation of space and vision, the ordinary methods are not suitable for minimal y invasive surgery. OBJECTIVE:To develop high frequency electrosurgical generator that has a constant power output and ability for tissue cutting and closing. METHODS:In order to improve the efficiency of tissue cutting and sealing in surgical, a kind of high-frequency energy generator was developed for tissue cutting and sealing. The instrument consisted of switching power supply with adjustable amplitude, high-frequency power amplifier, impedance monitor and microcontrol er. The energy converter composed of switching power supply and high-frequency power amplifier converted the 220 V, 50 Hz utility powers to a kind of high-frequency energy with 450 kHz and applied on tissues. Impedance monitor would real-timely detect the electrical parameter impacting on tissue that was provide the amount of feedback to microcontrol er in order to complete constant power control and bioimpedance determination by the control er. RESULTS AND CONCLUSION:The experimental results indicated that the instrument could rapidly and stably provide high-frequency energy, and could detect the biological impedance in real-time, achieve constant power output through feedback control, and could cut and close the biological tissue efficiently.