Genkai 元海 (1093–1156) was a senior Japanese Shingon master of the late Heian period, of the Daigo-ji / Hannya-ji 般若寺 transmission line. He rose to the rank of Sōjō and held the abbacy of Hannya-ji — the same temple where his great predecessor Gangō 元杲 had earlier served (see KR6t0176 etc.). He was the religious counselor of senior nobles of the Toba 鳥羽 / Sutoku 崇徳 / Konoe 近衞 cloistered-emperor courts in the second quarter of the 12th century, and personally performed the Vajra rain-prayer rite on multiple occasions for the imperial court.
His scholarly notebook KR6t0189 Hòu zào zhǐ — the “Thick-Paper Notebook” — preserves a remarkable diary-record of dated imperial ritual performances spanning 1117–1147, making it one of the most concrete documentary witnesses to actual kōke on-inori practice in that period.
Surviving work in the Kanripo corpus: KR6t0189 Hòu zào zhǐ (1 fasc.).