Yax Mayuy Chan Chaak was a ruler of the Maya city of Naranjo who is mentioned on Naranjo stelae 18 and 46. He was the king after K'ak' Tiliw Chan Chaak, who was possibly his older brother or his father. On August 15, 725 CE, he participated in a poorly-understood ritual at Naranjo with the otherwise-unknown Yax Bajlaj Chan Chaak, according to Stela 46; this ritual may have been a type of recognition of the heirship to the throne.