Snow scorpionflies are notable for their unusual activity during the cold winter months as adults. Although widely distributed in boreal or high-altitude areas of the Palearctic and Nearctic Regions, their presence in China has not been documented until now. This paper reports the first discovery of three species of snow scorpionflies, Boreus altaicus Nikolajev, 2015, B. beybienkoi Tarbinsky, 1962, and B. transiliensis Nikolajev, 1998 from Xinjiang Uygur Autonomous Region, northwestern China, and provides new insights into their morphology and biology. These discoveries increase the number of known Mecoptera families in China from three to four.