An experimental investigation has been conducted to study the effect of surface tension on phase distribution of gas-liquid two-phase flow through a T-junction with diameter 0.5 mm. It is found that the decrease in liquid surface tension makes the liquid taken off reduce when inlet flow pattern is slug flow, slug-annular and annular flow. These results highlight that phase distribution is remarkably influenced by surface tension in micro-T-junctions. To be specific, the surface tension contributes positively to liquid taking off. High surface tension seems to make the liquid capture more kinetic energy transported from the gas and dissipate it in form of vortexes. It is suggested that phase distribution in micro-T-junctions can be partly controlled by adjusting liquid surface tension. (C) 2011 Elsevier Ltd. All rights reserved.