Lady Zac-Kuk (sometimes rendered as Sac K'uk' ) was Queen of the Maya state of B'aakal, now known as Palenque, in what is now eastern Mexico.
Her father was Pacal I. As Pacal I seems to have had no male heirs, she accended to the throne on 22 October 612, a few months after her father's death. After his maturity, her son Pacal II, better known as Pacal the Great, succeded her as ruler on 29 July 615. She seems to have continued to have had considerable influence over Palenque in the early decades of her son's reign. Lady Zac Kuk died on 12 September 640.