is a subregion of the Chà «bu region in Japan consisting of Yamanashi, Nagano, and Niigata prefectures.
The name Kà Âshin'etsu is a composite formed from the names of old provinces which are adjacent to each other — Kai (now Yamanashi), Shinano (now Nagano) and Echigo (now Niigata). The region is surrounded by the Sea of Japan to its north west, Hokuriku region to its west, Tà Âkai region to its south west, Kantà  region to its south east, and Tà Âhoku region to its north east. The name for this geographic area is usually combined with Kantà  region (as in "Kantà Â-Kà Âshin'etsu"); and it is sometimes combined with Hokuriku region (as in "Kantà Â-Kà Âshin'etsu-Hokuriku" or "Hokuriku-Kà Âshin'etsu").
The KÃ Âshin'etsu subregion economy is for almost all purposes the same as the Shin'etsu subregion economy. The economy of KÃ Âshin'etsu subregion is large and highly diversified with a strong focus on silverware, electronics, information technology, precision machinery, agriculture and food products, and tourism. It also produces crude oil. Until 1989, the KÃ Âshin'etsu subregion also partook in gold mining, particularly at Sado Island.
Per Japanese census data, KÃ Âshin'etsu subregion has had negative population growth since 2000.