Frying stability of two virgin (VSO) and refined (RSO) sesame oils was compared with that of a refined olive oil (ROO). The oils were used to fry potato stripes at 180 °C and conjugated dienes (CDV), total carbonyls (CV), and thermo-oxidative and hydrolytic polar components were monitored over time. The rate of change in CDV (mmol l–1 h–1) was significantly lower for ROO (0.72) than for VSO (1.00) and RSO (1.84). The change in CV for ROO (2.31 μmol g–1 h–1) was significantly much faster than those for RSO (1.89) and VSO (1.17). Based on the thermo-oxidative polar components, the calculated frying times for VSO, RSO, and ROO were on the order of 32.1, 13.9, and 15.4 h. However, VSO contained significantly the highest contents of hydrolytic polar components over time and RSO exhibited more resistance than ROO on this basis.