Current requirements to stock tank oil quality promote development and improvement of oil treatment technologies. One of the promising methods is enhancement of hydrogen sulfide stripping via ultrasonic treatment. Experimental studies have been carried out to determine the efficiency of ultrasonic radiation under various conditions. The efficiency increases with temperature growth, especially for high-viscosity oils. For oil viscosity over 400 MPa·s, specific sound power increase has little or no impact on H2S stripping, while in case of viscosity below 150 MPa·s increase of sound power from 100 to 200 kW/m3 enhances hydrogen sulfide separation twofold. Increase of ultrasonic exposure time also contributes to a more complete H2S removal. However, increase of exposure time and specific sound power is not always economically viable. An optimum exposure time is from 4 to 17 minutes at specific sound power of 10-50 kW/m3 . The obtained results show that ultrasonic oil treatment improves transition of hydrogen sulfide from oil to the gas phase and can be used at thermal stages of separation to reduce consumption of H2S chemical scavenger.