Baron Katō Hiroyuki (加藤 弘之, August 5, 1836 – February 9, 1916) was an academic and politician of the Meiji period Japan.

[1] Katō was born on August 5, 1836, to a samurai family in Izushi domain, Tajima Province (present day Hyōgo Prefecture), and studied military science under Sakuma Shōzan and rangaku under Oki Nakamasu in Edo.

After the Meiji Restoration, Katō wrote numerous theses recommending Japanese adoption of Western forms of government, especially that of a constitutional monarchy with a national assembly based on representative democracy.

He joined the Rikken Seiyūkai political party, and was also a founding member of the Meirokusha intellectual society organized by Mori Arinori.

As a member of the Genroin, he strongly supported Statism, a much more authoritarian version of government against the views propounded by the Freedom and People's Rights Movement.