The total polyphenols of Kyllinga Brevifolia Rottb was extracted by adding surfactant. With the extraction of total polyphenols as index to determine the added surfactant species, Twelve Sodium Alkylbenzene Sulfonate(SDBS) was the best in seven kinds of surfactants. Several single factor extraction conditions were examined including the concentration of surfactant, ultrasonic time, ultrasonic temperature and ethanol concentration. On the basis of as mentioned determined data, Orthogonal experimental method was adopted and the optimal extraction conditions  were ultrasonic time of 30min, ultrasonic temperature of 50 DEG C, 65% ethanol concentration, ethanol concentration is 65%, the total polyphenols extraction rate was 5.787% under these conditions; 5 groups of parallel experiments were carried out, the average extraction rate of total polyphenols was 5.776% with the relative error of 0.187%.Compared with no surfactant, the extraction rate of total polyphenols was increased by 64.5%. The method of adding surfactant to extract total polyphenols is feasible.