In many industrial bioprocesses, the key parameter is the oxygen mass transfer capability of the bioreactor. The bottleneck in such processes is the low solubility of oxygen in aqueous media (8-10 ppm). This decreases the Oxygen Transfer Rate (OTR). Literature showed that the addition of organic liquids to the bioreactor as the second liquid phase could enhance OTR, if the oxygen solubility in the second liquid phase is higher than that in aqueous media. In this study, palm oil was chosen as the organic phase, because it is abundantly available in Malaysia. Experiments were carried out in two model media viz., xanthan gum solution and distilled water with the addition of palm oil to evaluate the effect on oxygen transfer. OTR was measured in terms of the volumetric mass transfer coefficient, kLa. Results indicated that the addition of the palm oil in the medium decreased the oxygen transfer coefficient.