Oiryo (Bureau of Palace Kitchens) is a bureau of Kunaisho (the Ministry of the Imperial Household) under the ritsuryo system (a system of centralized government based on the ritsuryo code) in Japan. Oi is said to be an abbreviated name of oikashigu.
The bureau was responsible for food preparation for Buddhist and Shinto ceremonies and feasts in the court and food management. It also managed the Imperial demesnes. Beginning in the Heian period, kami (the head) was inherited by the Nakahara clan.
One kami (equivalent to Jugoinoge [Junior Fifth Rank, Lower Grade])
One suke (equivalent to Jurokuinojo [Junior Sixth Rank, Upper Grade])
One jo (equivalent to Jushichiinojo [Junior Seventh Rank, Upper Grade])
One daisakan (equivalent to Juhachiinoge [Junior Eighth Rank, Lower Grade])
One shosakan (equivalent to Daihatsuinojo [Greater Initial Rank, Upper Grade])
Oibe were zoshikinin (lower-level functionaries in the provincial government) who cooked rice and manage rice stores. Kanninzonin (lower-ranking government official) was a new post.
Tsukaibe (low rank bureaucrats)
Kanninshicho (a manservant doing odd jobs)
Kushicho (general workers)
Kugoin (Division of rice for the Emperor)
Shisho (a person doing miscellaneous duties about documents) of Oiryo controlled Kugoin as Kugoin-azukari. Kugo means meals for the emperor and kugoin was responsible for cooking meals for the imperial family including the emperor, retired emperors, princes and empresses, and for food preparation and management.