Jejomar Binay also was sworn in as vice president, with his wife, Dr. Elenita Binay, holding the Bible as the rest of his family watched, the Philippine Daily Inquirer.net reported.
Watching as Associate Justice Conchita Carpio-Morales administered the presidential oath were Aquino's sisters -- Ballsy, Pinky, Viel and Kris -- and his girlfriend, Valenzuela councilor Shalani Soledad.
Thousands of people wearing the Aquino family's signature yellow braved stormy weather to gather before dawn at the Quirino Grandstand in Manila for the inauguration, the Daily Inquirer reported online.
Aquino's predecessor, Gloria Macapagal-Arroyo, drew a mixed reaction from the crowd, with some clapping and cheering and others booing her. However, applause and cheers erupted when Arroyo and Aquino shook hands and shouts of "Noynoy" -- Aquino's nickname -- filled the air, the newspaper said.
Aquino claimed victory May 10 on a pledge to end corruption and fight poverty he said thrived during the nearly the 10 years Arroyo led the country. Aquino is the son of Philippine democracy heroes Benigno and Corazon Aquino, still revered for their efforts to overthrow dictator Ferdinand Marcos. His mother, Corazon, also earned a reputation as incorruptible during her six years as president following the "people power" revolution that ousted Marcos in 1986.