Yamagata Prefecture (山形県, Yamagata-ken) is a prefecture of Japan located in the Tōhoku region of Honshu. Yamagata Prefecture has a population of 1,079,950 (1 June 2019) and has a geographic area of 9,325 km² (3,600 sq mi). Yamagata Prefecture borders Akita Prefecture to the north, Miyagi Prefecture to the east, Fukushima Prefecture to the south, and Niigata Prefecture to the southwest.
Yamagata is the capital and largest city of Yamagata Prefecture, with other major cities including Tsuruoka, Sakata, and Yonezawa. Yamagata Prefecture is located on Japan's western Sea of Japan coast and its borders with neighboring prefectures are formed by various mountain ranges, with 17% of its total land area being designated as Natural Parks. Yamagata Prefecture formed the southern half of the historic Dewa Province with Akita Prefecture and is home to the Three Mountains of Dewa, which includes the Haguro Five-story Pagoda, a recognised National Treasure of Japan.