Abstract Ultrasonic evaporator is a new type of evaporation equipment using ultrasonic technology to assist evaporation and concentration. It is especially suitable for the materials which are easy to scale and foam. Due to the complexity of heat and mass transfer during ultrasonic technology to assist liquid evaporation process, there are few reports on the energy consumption of ultrasonic evaporation. In this paper, the effects of ultrasonic density, evaporation temperature, and feed flow rate on the total energy consumption of ultrasonic evaporation were studied and tap water was selected as experimental material. It was found that the optimal condition for this ultrasonic evaporator were the ultrasonic power density of 4 × 10−5 W/m2, the evaporation temperature of 65 °C, and the feed rate of 1.389 × 10−5 m3/s. According to the orthogonal test and analysis of variance, it can be obtained that the influence of evaporation temperature on total energy consumption is the largest, the second is feed flow rate, and ultrasonic power density has the least influence.