Objective To investigate the distribution of vectors of mosquito?borne diseases in the Hexi Corridor of Gansu province, China and to further confirm the Hexi Corridor as the area free of Japanese encephalitis (JE) and other mosquito?borne diseases. Methods The light?trap method and labor hour method were used to capture mosquitoes. In the light?trap method, the suction?type mosquito lamp (Kung Fu Xiaoshuai) was hung 0.8-1.5 m above the ground at each investigation point, and the mosquito lamp worked for 12 hour each time. In the labor hour method, the hand?held electric mosquito trap or mouth suction?type mosquito trap was used to capture mosquitoes in the human house, residential passageway, pigsty, and cowshed for 30-40 min. Results A total of 23 584 mosquitoes were collected, which, as preliminarily identified, belonged to 18 species and 4 genera. Most of the captured mosquitoes were from animal houses, accounting for 76.39%, followed by farmer’s households, accounting for 14.23%, and the last one was residential area, from which 4.49% of mosquitoes were captured. Culex pipiens pallens and Aedes vexans were the dominant species, which accounted for 55.87% and 23.04%, respectively, of all mosquitoes and were distributed almost throughout the 5 cities in Hexi Corridor area. Culex tritaeniorhynchus, the main vector of JE, was not captured, and JE virus was not detected. However, mosquito?borne flavivirus and Liaoning virus were first found in this area, with a relatively high detection rate. Conclusion Various species of mosquitoes are widely distributed in the Hexi Corridor, and the mosquito population density is relatively in raprian areas. Cleanup of mosquito breeding sources should be strengthened, and the research on mosquito?borne viruses in the Hexi Corridor cannot be neglected.