{{Short description|Japanese politician (1855–1935)}} {{family name hatnote|Ōishi|lang=Japanese}} {{Unreferenced|date=March 2026}} {{Infobox officeholder | honorific_prefix = Senior Third Rank | name = Ōishi Masami | native_name = {{Nobold|大石 正巳}} | native_name_lang = ja | image = Ōishi Masami.jpg | caption = | office = Minister of Agriculture and Commerce | prime_minister = Ōkuma Shigenobu | term_start = 30 June 1898 | term_end = 8 November 1898 | predecessor = Kaneko Kentarō | successor = Sone Arasuke | office1 = Member of the House of Representatives | constituency1 = Mie 4th (1898–1902)<br>Mie Counties (1902–1903)<br>Kōchi Counties (1903–1914) | term_start1 = 10 August 1898 | term_end1 = 25 December 1914 | predecessor1 = Yatsuchi Kazuyuki | successor1 = Ishimoto Kantaro | birth_date = {{birth date|1855|05|26|df=y}} | birth_place = Tosa Province, Japan | death_date = {{death date and age|1935|07|12|1855|05|26|df=y}} | death_place = | resting_place = Aoyama Cemetery | alma_mater = | party = Rikken Dōshikai (1913–1915) | other_party = Liberal (1881–1882)<br>Shimpotō (1896–1898)<br>Kensei Hontō (1898–1910)<br>{{nowrap|Rikken Kokumintō (1910–1913)}} }} {{nihongo|'''Ōishi Masami'''|大石 正巳| |extra=26 May 1855 – 12 July 1935}} was a politician and cabinet minister in the pre-war Empire of Japan.
==Biography== Ōishi was a native of Tosa Province (modern-day Kōchi Prefecture), where his father was a samurai in the service of Tosa Domain. In 1873, he joined with Itagaki Taisuke and became an important member of the Freedom and People's Rights Movement. He became one of the leaders of the ''Jiyūtō'' political party in 1881. However, he had a falling out with Itagaki in 1882 and left the party. He subsequently joined with Gotō Shōjirō’s ''daidō danketsu'' (coalition) movement in 1887. In 1892, he was appointed to the Japanese legation in Seoul, Korea. He was back in Japan by 1896, and was one of the founding members of the ''Shimpotō'' political party. Under the short-lived 1st Ōkuma Shigenobu administration in 1898, Oishi was appointed Minister of Agriculture and Commerce.
Ōishi later joined the ''Rikken Kokumintō'' and was at one point a contender against Inukai Tsuyoshi for its leadership. In 1913, he broke with Inukai, and joined Katsura Tarō’s new Rikken Dōshikai, where he was ranked as one of its five leaders. He retired from politics in 1915, after having been elected to the Lower House of the Diet of Japan for six terms.
{{s-start}} {{s-off}} {{succession box | before=Kaneko Kentarō | title=Minister of Agriculture & Commerce | years=30 June – 8 November 1898| after=Sone Arasuke}} {{s-end}} {{Authority control}}
{{DEFAULTSORT:Oishi, Masami}} Category:1855 births Category:1935 deaths Category:Politicians from Kōchi Prefecture Category:Government ministers of Japan Category:Members of the House of Representatives (Empire of Japan) Category:Shimpotō politicians Category:Liberal Party (Japan, 1881) politicians Category:Rikken Kokumintō politicians Category:Rikken Dōshikai politicians