Seishi

{{Infobox given name

| name = Seishi

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| gender = Male

| meaning = Different meanings depending on the kanji used

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| origin = Japanese

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Seishi (written: 聖史, 正士, 正史 or 誠志) is a masculine Japanese given name. Notable people with the name include:

• {{Nihongo|Seishi Kanetsuki|金築 誠志}} (born 1945), Japanese jurist
• {{Nihongo|Seishi Kikuchi|菊池 正士}} (1902–1974), Japanese physicist
• {{Nihongo|Seishi Kishimoto|岸本 聖史}} (born 1974), Japanese manga artist
• {{Nihongo|Seishi Yokomizo|横溝 正史}} (1902–1981), Japanese writer
• {{Nihongo|Seishi|聖師}} {{Nihongo|Onisaburo Deguchi|出口王仁三郎}} (1871–1948), Japanese spiritual leader