The effect of gas sparger design on the gas holdup radial profile in a bubble column (with a diameter of 0.162 m) has been studied using gamma-ray computed tomography (CT). Six different configurations of gas spargers were examined, using an air-water system for selected superficial gas velocities from 2 cm/s to 30 cm/s, covering the homogeneous and heterogeneous (churn -turbulent) flow regimes. Two operating pressures were used: I and 4 atm. Differences were found between the gas holdup distributions produced by different spargers at dimensionless radii of r/R < 0.8 in the central region of the column. The cross and single nozzle spargers produced closely similar gas holdup distributions, while the perforated plate sparger produced a higher gas holdup when compared to other spargers with the same percentage open area (POA). At 4 atm, the sparger design did not have a significant effect on the gas holdup profiles, compared to atmospheric pressure, except for the case of the single-hole sparger, which was found to yield a higher gas holdup.