The gas chamber is an integral part of various gas-liquid equipment such as packed columns, plate columns, bubble columns, etc. CFD simulation of the flow pattern was carried out in a gas chamber of square cross-section and provided with sieve-plate distributor. Velocities through all the holes were estimated for assessing the uniformity of the gas chamber distribution. The aspect ratio and superficial gas velocity were varied in the range of 0.5 to 4 and 0.02 to 0.2 m/s respectively. The effects of free area and hole diameter were investigated in the range of 0.6 to 6% and 3 to 9 mm respectively. The role of nozzle size and its location with respect to the distributor was analyzed on the uniformity of gas distribution.