The invention discloses hot and sour purple potato noodles which are made from, by weight, 900-1,000 parts of flour, 0.6-0.7 part of loquat flowers, 0.9-1 part of amomum tsao-ko, 0.5-0.6 part of fructus aurantii immaturus, 0.7-0.8 part of flos magnoliae, 30-32 parts of pteridium aquilinum, 15-19 parts of white vinegar, 20-23 parts of peppers, 40-45 parts of purple potatoes, 7-8 parts of salt, 0.5-0.6 part of glucose oxidase, 60-65 parts of soybean protein powder, 9-10 parts of oxidized potato starch and a proper amount of theaflavin. The noodles are good in quality and taste, bright in color, rich in nutrient, hot, sour and refreshing in taste and capable of stimulating appetite and digestion. The added pteridium aquilinum has anti-diarrhea and diuretic functions, and the contained dietary fibers can promote gastrointestinal motility and has the functions of regulating qi, relaxing the bowels and expelling toxin. The noodles can also be used for treating rheumatic arthritis, dysentery, hemoptysis and other diseases and have a measles and flu prevention function.