The local gas holdup profiles in an internal-loop airlift reactor were studied experimentally by using dual electrical conductivity probe under different conditions，including superficial velocity，surface tension and liquid viscosity.The results showed that the radial gas holdup profile has a parabolic shape，which was consistent with the empirical model of Luo.Local gas holdup distribution parameters were obviously influenced by flow regime and almost remained unchanged in the same flow regime.In the gas distributor region，the profiles were steeper in the homogenous flow regime than in the heterogeneous flow regime.However，in the stable region，there was an inverse change trend in two flow regimes.The increase of surface tension，superficial velocity and liquid viscosity made the profile of local gas holdup steeper in two flow regimes.