The simultaneous ultrasonic/microwave assisted extraction (UMAE) technology of extracting antioxidants from clove was optimized and the reason for high-efficiency of this method was analyzed. The results show that the optimal parameters of the UMAE technology were as follows, ethanol concentration was 50%, ratio of extracting solution to sample was 30mL/g, ultrasonic power was 50W, the microwave power was 100W and the extracting time was 12min. Comparative study show that the extraction ratio of antioxidants from clove by UMAE was significantly improved compared with water bath oscillator extraction (WBOE) in the same conditions. It was also found that the superiority of UMAE was simultaneously acted and mutually reinforced by ultrasonic and microwave through interaction analysis. A comparison of scanning electron microscopy images from the clove powders by UMAE, WBOE, microwave assisted extraction (MAE) and ultrasonic assisted extraction (UAE) indicated the extraction efficiency was higher by UMEA with the more serious disruption of cell structure and the more sufficient interaction.