Marquis Yi of Cai (è¡夷侯) (died 809 BC), birth name unknown, was the seventh ruler of the State of Cai from 837 BC to 809 BC. He was the only known son of Marquis Wu of Cai (è¡æÂ¦ä¾¯). His reign lasted for 28 years like his father's. He was succeeded by his son.