The study on hydrodynamics and mass transfer performance is carried out in a 25 mm diameter continuous countercurrent supercritical fluid extraction spray column. The range of experimental pressure is from 8 to 14 MPa and the temperature is 35℃. The testing systems arecarbon dioxide-isopropanol-water and carbon dioxide-ethanol-water. A model for describing two-phase flow in the supercritical fluid extraction spray column is obtained. A new model based on two film theory for calculating overall volumetric mass transfer coefficient is developed. Both of the two models match experimental data well.