The invention discloses high-content buckwheat fine dried noodles and a preparation method thereof. The high-content buckwheat fine dried noodles are prepared from buckwheat whole flour, high-gluten wheat flour, wheat gluten, resistant starch, egg white powder, sodium alginate, konjac flour, sodium carbonate, glutamine transaminase, hemicellulase and phytase. The preparation method comprises the following technical steps: pretreatment of buckwheat raw materials, optimization of proportions of raw and auxiliary materials, vacuum dough mixing, an improved rolling press process, cutting into noodles by a knife, hanging on a rack, drying, cutting of long noodles, packaging and the like, thereby obtaining the high-content buckwheat fine dried noodles. By intensifying protein crosslinking by anenzyme modification technique, improving the content of soluble dietary fibers and biologically degrading an anti-nutritional factor phytic acid, the preparation method effectively improves the utilization ratio of nutrient substances and the high-content buckwheat fine dried noodles have the effects of controlling generation of postprandial blood sugar, preventing obesity and the like; and in addition, the high-content buckwheat fine dried noodles do not contain edible salt in a formula, belong to low-salt products, are in line with the concept of modern healthy diet, and are healthy type high-content buckwheat fine dried noodles.