Abstract: The change of temperature in oil and frozen oil during microwave reheating was determined by microwave workstation. The effects of different freezing conditions on temperature changing of oil and frozen oil during microwave reheating were investigated. Results showed that there were differences between heating characteristics of 6 kinds of oil, heating rate of the sunflower oil was higher since it contained more unsaturated fatty acid, but the peanut oil was on the contrary. Frozen for 1 day under-20℃, reheating curves of the 6 kinds of oil were all presented the “S ” pattern, but the heating rate of peanut oil was lowest, because its freezing point was the highest, which means it need more time to reach 0℃. The soybean oil was stored at-20℃ and-30℃ respectively for a month, and reheated regularly, finally found the lower frozen temperature the smaller impact on the temperature change of oil after microwave heating, when under the same freezing temperature, impact decreased with freezing time increased.