Sunflower oil is faced with serious problems including oxidation during the deep-frying of Chinese Maye, so a search for natural antioxidants is quite necessary. In the present study, after deep-fried for 30 h, the addition of the essential oil of the aerial parts from M. spicata cv. Henanshixiang (MSEO) to sunflower oil at 0.08 g/kg not only significantly restrained the increase of total polar compounds (TPC), thiobarbituric acid (TBA), conjugated dienes, conjugated trienes, polymer and viscosity of sunflower oil by 48.4%, 41.4%, 64.6%, 42.4%, 61.8 and 26.7% (p < 0.01 or p < 0.05), respectively, but also prominently restrained the decrease of the sensory properties of the fried product, Chinese Maye, including flavor, taste, crispness and overall acceptance by 26.2%, 25.3%, 59.0% and 41.6% (p < 0.01 or p < 0.05), respectively. Furthermore, by means of bioassay-guided fractionation and the repeated deep-frying process, one compound of MSEO, limonene, was demonstrated to increase the oxidative stability of sunflower oil. The result revealed that limonene was the key antioxidant compound in MSEO, and it could be used to replace synthetic antioxidants during the deep-frying of Chinese Maye using sunflower oil.