Abstract: Extracting technique assisted by ultrahigh pressure extraction method of flavonoids from hawthorn was optimized. The total yields of rutin, hyperin, and quercetin were used as response value, ethyl alcohol volume percentage, liquid to solid (L/S) ratio, power, and retention time were investigated in this experiment.The results showed that the sequence of different factors on flavonoid yield was:ethyl alcohol volume percentage>retention time>L/S ratio>power;and the mathematical model of ultrahigh pressure extraction hawthorn flavonoid extraction was established, the optimal condition was that ethyl alcohol volume percentage 90%, L/S 24∶1m L/g, ultrahigh pressure 500 MPa, retention time 12 min, under the optimal condition, the hawthorn flavonoid yield was0.0553%. Compared with sohxlet extraction method and ultrasonication extraction, there was obvious advantage at extracting time and extracting efficiency, it was observed from the scanning electron microscopy (SEM) that the destroy was more serious after treated by ultrasound and ultrahigh pressure than by long time sohexlet extracting, intracellular substances were dissoluted easier, and higher extraction efficiency was achieved within a short time.