A modified two-fluid theoretical model is presented to describe the two-dimensional liquid phase flow on a sieve tray with consideration of the resistance created by uprising vapour, and solved numerically by the method of controlled volume. A sieve tray simulator is used for the experimental verification in which the local two-dimensional velocities of the liquid phase are measured by an improved technique using the hot him anemometer. The experimental results show that the liquid phase flow on a tray is substantially two-dimensional if the measurement is made more than 10 mm above from the tray floor, below which the flow is found to be three-dimensional. A comparison between the theoretical computations using the present model, the experimental results produced by the authors and those from the literature indicates that the proposed model gives a good prediction fur the two-dimensional liquid phase flow on a tray under normal operation. Factors affecting the liquid phase circulating flow are discussed.