Abstract: Flow pattern or velocity distribution on a distillation tray is of great importance in determining tray efficiency. And design of distillation process is mainly rely on experimental data which also can be used in verification of mathematical model for describing the flow pattern on a tray.In this paper,hot-film anemometer with X-type probe is applied to the measurement of gas-liquid two-phase flow on a sieve tray.First,a calibration method that used in this paper is proposed and a computational model for data processing is presented.Then the threshold method used to separate vapor signals from those of the liquid is described.Finally,typical measuring results,which include the magnitude and direction of local velocity,and the distribution of turbulent kinetic energy,are presented.