齋藤道三
was a Japanese samurai of the Sengoku and Azuchi-Momoyama periods. Originally a retainer of Saitō Dōsan, Mitsuharu went on to serve Oda Nobunaga, he received a land in Echizen Province and became a member of the so-called Sanninshu (Echizen Triumvir) along with Maeda Toshiie and Sassa Narimasa.