Koahou (died 1826) was a Hawaiian high chief who succeeded his father Kamanawa as one of the chief counselors of Kamehameha I. He was the son of High Chief Kamanawa and High Chiefess Kekelaokalani.His father Kamanawa, along with Koahou's uncle Kameʻeiamoku, were known as the "royal twins" and helped Kamehameha I come to power and served him as advisors.His mother Kekelaokalani was the daughter of High Chief Kauakahiakua, son of Lonomakahonua and Kahapoohiwi, and High Chiefess Kekuʻiapoiwa I, the former wife of King Kekaulike of Maui.His siblings included two brothers: Noukana and Amamalua, a sister Peleuli, who became one of the wives of Kamehameha I, and a half-sister Piʻipiʻi Kalanikaulihiwakama.