Saitō Dōsan, Japanese samurai (b. 1494)
Saitō Dōsan (斎藤 道三, 1494 – May 28, 1556), also known as Saitō Toshimasa (斎藤 利政), was a Japanese samurai during the Sengoku period.

He was also known as the "Viper of Mino" (美濃の蝮, Mino no Mamushi) for his ruthless tactics. His honorific title from the Imperial Court was Yamashirō-no-kami (山城守). After entering monkhood in his later years, he was also called Saitō Yamashirō-nyudō-no-kami (斎藤山城入道守).