In this paper, the flow field inside a square channel with a two-stage electrohydrodynamic (EHD) gas pump has been critically examined by experimental measurement and numerical simulation. The EHD gas pump with 28 emitting electrodes in each stage is tested for a wide range of operating voltages starting from the corona onset voltage up to 28 kV for further improvement in its performance over a single-stage one. It has been shown that the two-stage EHD gas pump can produce and sustain gas flows with a maximum velocity of 1.8 m/s. Its maximum performance of 36 L/s/W is better than that of conventional cooling fans used in personal computers. The implication for its application in thermal management and heat transfer enhancement has also been discussed.