Nikko Shugen, one of the sects of Shugen-dō, is believed to have been introduced in Nikko from Kumano, where Kumano Shugen exists, by Benkaku Hoin, the 24th chief abbot of Mt. Nikko. In this paper, I transcribe the music of an esoteric ritual Saitō Dai Gomaku from Nikko Shugen into a musical score. Analyzing the music in Gomaku, I establish that it contains the Teketetton rhythm pattern that is a part of Sato Kagura which can be found throughout East Japan. Interestingly, the same rhythm pattern can be observed in the step rhythm of the Rinnoji temple dance, Ennen no Mai, in Nikko. In an earlier article, I proposed that this rhythm pattern is derived from the Age Byōshi rhythm pattern in the Komagaku dance music of the ancient Korean peninsula. Therefore, my analysis on the music in Nikko Shugen in this paper is an introduction to “music ethnography,” which considers not only the connection between Japanese regional music, but also the connection between music from various tribes across the world.