Kasuga Shrine is a Shinto shrine at the base of Mt. Kasugayama. The mountain was named after the shrine, which stood at the top of Mt. Kasugayama for roughly 500 years until 1452, when it was relocated to make way for Kasugayama Castle. It served as the guardian of the castle, which was the stronghold of famed warlord Uesugi Kenshin (1530–1578). Its new location was to the northeast of the castle, a direction traditionally regarded as inauspicious. The location was chosen so that the deity could ward off evil spirits thought to come from that direction.

The origins of the shrine can be traced back to the Nara period (710–794), when officials from Nara, the capital at the time, arrived in Echigo Province (present-day Niigata Prefecture) to govern the area. The officials are said to have found that Mt. Kasugayama resembled the sacred Mt. Mikasa in Nara, the mountain adjacent to Kasuga Taisha Shrine, the guardian of the eighth-century capital city. They therefore decided to establish a new Kasuga shrine on top of the mountain. Founding branch shrines in this way has been a common practice throughout Japanese history, and there are currently more than 3,000 Kasuga shrines nationwide.

Kasuga Shrine was completely reconstructed in 2020, its first major restoration since a fire roughly 200 years earlier, with donations from local residents and businesses. The shrine hosts a festival each spring.