Waipiʻo (Hawaiian pronunciation: [vɐjˈpiʔo]) is a census-designated place (CDP) located on the island of Oʻahu in the City & County of Honolulu, Hawaii, United States.

"[3] Waipi'o is located at 21°25′5″N 157°59′53″W / 21.41806°N 157.99806°W / 21.41806; -157.99806 (21.418050, -157.997988),[4] south of Mililani Town via either Interstate H-2 or Kamehameha Highway (Hawaii Route 99).

According to the United States Census Bureau, the CDP has a total area of 1.2 square miles (3.1 km2), all of it land.

The Hawaii Department of Public Safety operates the Waiawa Correctional Facility, a minimum security prison near Waipio.

[9] On September 10, 2019, the 45.9 megawatt Waipiʻo Solar developed by Clearway Energy Group began its operation.

San Francisco-based Clearway's predecessor the NRG Energy's Community Solar division, took over the project at the end of November 2016.

Waipio is the second team from the Ewa District to win the world championship; 'Ewa Beach representing West O'ahu won the title in 2005.

[14][15][16] In 2010, the Waipio LL team won the U.S. championship of the Little League World Series, defeating Pearland White LL from Pearland, Texas on August 28, 2010, by a score of 10-0 after 5 innings, which invoked the Little League "mercy rule" where a team is leading by 10 runs or more after 4 innings.

They lost in a close 4–1 game to Edogawa Minami LL of Tokyo, Japan on August 29, 2010, in the Series final.