Viscount Hamao Arata (?? ?, May 12, 1849 – September 25, 1925) was a Japanese politician and educator of the Meiji period, originally hailing from Toyooka, Hyogo.
He was active in the Monbu-sho (present Monka-sho) and as the president of institutions such as Tokyo Imperial University.
Hamao was also, very briefly, Lord Keeper of the Privy Seal of Japan.
He was ennobled as a baron on 23 September 1907 and advanced to viscount on 25 November 1921.