Yūki(結城郡,Yūki-gun?) is a district located in Ibaraki Prefecture, Japan. As of May, 2008, the district has an estimated Population of 23,388 and a Density of 396 persons/km². The total area is 59.1 km².
The district contains one town, Yachiyo(八千代町,Yachiyo-machi?)
April 1, 1889 - Due to the municipal status enforcement, the town of Yūki and the villages of Kinugawa, Egawa, Kamiyamakawa, Yamakawa, Nasaki, Nakayūki, and Shimoyūki were formed within Yūki District. (1 town, 7 villages)
April 1, 1896 - Yūki, Okada, and Toyoda Districts merged to form the new Yūki District. (2 towns, 25 villages)
August 24, 1897 - The village of Ishige gained town status to become the town of Ishige. (3 towns, 24 villages)
March 14, 1954 - The village of Yamakawa merged into the town of Yūki. (3 towns, 23 villages)
March 15, 1954 - The town of Yūki absorbed the villages of Kinugawa, Egawa, and Kamiyamakawa and gained city status to become the city of Yūki. (2 towns, 20 villages)
June 1, 1954 - The villages of Fusakami and Toyokami merged into the town of Shimotsuma, Makabe District. The town of Shimotsuma gained town status to become the city of Shimotsuma on the same day. (2 towns, 18 villages)
July 10, 1954 - The town of Mitsukaido absorbed the villages of Toyooka, Sugawara, Ōhanawa, Mitsuma, Goka, Ōnoo, and 坂手, Kitasōma District, and gained city status to become the city of Mitsukaido. (1 town, 12 villages)
October 1, 1954 (1 town, 8 villages)
Parts of the village of Tama merged into the village of Sōdō.
The town of Ishige and the villages of Toyoda, Okada, Iinuma, and the remaining parts of Tama merged to form the town of Ishige.