Abstract: The separation experiment of CO₂, H₂O and O₂ with polysulfone hollow fiber membrane has been performed by varying the pressure and flow rate with a newly set-up experimental platform at 24℃. The inlet gas for membrane is from atmosphere compressed by compressor. After monitoring the concentrations of the feed gas, product gas and permeation gas by adjusting the pressure and flow rate in the gas stream, the parameters, including rejection ratio, mass transfer coefficient and permeability coefficient, are calculated to evaluate the separation performance of the membrane. The experimental results show that this kind of polysulfone membrane can manifestly remove these three components and has a good effect. The rejection ratio and feed gas flow rate are both more than 95% and 2 m³/h under the pressure of 320 kPa with these experimental circumstances, respectively.