The invention discloses a method for extracting low-methoxy pectin from apple pomace, comprises the following steps: washing apple pomace by using water at 30-40 DEG.C, microwave treating at 380-500 W and then filtering, microwave drying, the filtered apple pomace, stoving and crushing to obtain apple pomace powder, mixing the apple pomac powder and acid water to perform microwave treatment at 480-500 W, concentrating centrifuged supernatant as concentrated solution, pouring the concentrated solution in an upright filled with active carbon, and collecting the filtrate; heating the filtrate to 5-10 DEG.C, adding alkali solution to regulate the pH value, adding the acid water in the obtained pectin concentration solution to regulate the pH value to 3-5, adding ethanol water in the pectin concentrated solution, mixing, standing and centrifuging to obtain the precipitate, washing by using the ethanol water for 7-8 times, washing, precipitating, vacuum freezing and drying to obtain a substance, namely, the low-methoxy pectin. The process is coherent and simple, the required reagent is reagent in common use, low in cost and easy to purchase; the extracting rate can achieve 7.9-9.4%, the esterfication degree is 38.7-41.4%, and the galacturonic acid content is 72-82%.