Daidōji Yūzan (大道寺 友山, 1639 – December 11, 1730) was a samurai and military strategist of Edo period Japan.
Among the works he wrote in his late years was the widely circulated Budō Shoshin-shū (武道初心集), an introduction to warrior ethics that was influential[citation needed] among middle- and lower-class samurai.
It has been translated into English by Arthur Lindsay Sadler as The Code of the Samurai (1941; 1988), William Scott Wilson as Budoshoshinshu: The Warrior's Primer[1] and by Thomas Cleary.
Yūzan studied the arts of war in Edo under Obata Kagenori, Hōjō Ujinaga (北条氏長), Yamaga Sokō and others.
Yūzan's son Daidōji Shigetaka (大道寺重高) became a retainer of the Fukui fief with a stipend of 300 koku.