Minamoto no Yoshimitsu (源 義光, 1045 – November 25, 1127), son of Minamoto no Yoriyoshi, was a Minamoto clan samurai during Japan's Heian Period. His brother was the famous Minamoto no Yoshiie. Minamoto no Yoshimitsu is credited as the ancient progenitor of the Japanese martial art, Daitō-ryū aiki-jūjutsu. Yoshimitsu is also known as Shinra Saburō (新羅 三郎).
According to Daitō-ryū's internal history, Yoshimitsu dissected the corpses of men killed in battle, and studied them for the purpose of learning vital point striking (atemi) and joint lock techniques. Daitō-ryū takes its name from that of a mansion that Yoshimitsu lived in as a child, called "Daitō", in Ōmi Province (modern day Shiga Prefecture).
For military service during the Later Three-Year War (1083–1087), Yoshimitsu was made lord of Kai Province (modern day Yamanashi Prefecture), where he settled. Yoshimitsu's great-grandson, Nobuyoshi, eventually took the surname "Takeda", and the techniques Yoshimitsu discovered would be secretly passed down within the Takeda clan until the late 19th century, when Takeda Sokaku began teaching them to the public.