Abstract: The ultrasonic effects on the evaporation process have been studied. The results showed that the ultrasonic field promoted evaporation rote with an increase of 2%-6% and averagely more than 4% depending on the parameters of the ultrasonic field and the temperature of the solution.The dynamics process of two-component evaporation process in ultrasonic field for water-ethanol and benzene-ethanol solution is analyzed.The results indicate a linear variation relationship existing between evaporation velocity and evaporation time.The linear relationship is more easily found when the volume ratio between the two components is closer to each other.By analyzing the process of gas-liquid balance as well as nucleus shaping and volstilization,the cavitation effect of ultrasonic field is revealed.The surface tension is reduced by ultrasonic field.So the potential energy to shape nucleus decreases and the internal energy exchange of solution is promoted.The probability of shaping nucleus in gasification increases and the evaporation process of the solution is strengthened thereby.