Sandai-Kyaku-Shiki is a term used to collectively refer to three Kyaku-Shiki acts (laws supplementary to the Ritsu-ryo, which were the statutes of the Nara and Heian periods) that were codified during the Heian era: the Konin-Kyaku-Shiki Act, the Jogan-Kyaku-Shiki Act and the Engi-Kyaku-Shiki Act.
三代格式（さんだいきゃくしき）とは平安時代に編纂された弘仁格式、貞観格式、延喜格式の三つの格式(きゃくしき、律令の補助法令)の総称である。