Common buckwheat flour, ultrafine buckwheat flour A and B, with 5%~30%, was added to wheat flour and mixed, respectively. The farinograph properties of mixed flour were analyzed. The sensory quality, cooking quality and texture characteristics of dry noodle made of mixed flour were studied. The results showed that: compared with common buckwheat flour, the water absorption of ultrafine buckwheat flour dough was increased, dough formation time and stability time were shorten, dough softness was increased, farinogram quality number was decreased, the sensory quality of noodle was improved because of adding ultrafine buckwheat flour. Adding buckwheat flour with 15% or less, the cooking weight of the noodles containing common buckwheat flour was higher than the others. Adding 15% ~30%, the cooking weight with ultrafine buckwheat flour A was higher. Adding with 5% ~30%, the cooking loss of ultrafine buckwheat flour A was the least. Because of buckwheat micronization, the firmness and shear power of buckwheat noodles were increased and the chewiness and toughness of noodles were enhanced.