Kenji Tomiki (1900–1979) is a Japanese aikido teacher and the founder of aikido style Shodokan, often referred to as Tomiki Aikido.
Tomiki was one of the early students of the founder of aikido Morihei Ueshiba, and also of Jigoro Kano, the founder of judo. In 1925, the year he joined Morihei Ueshiba, he obtained 5th dan in judo. In 1929 he represented Miyagi Prefecture in the first judo tournament held in front of the Emperor - this tournament became the All Japan Tournament the following year. From 1936 till the end of the second world war he lived in Manchukuo (Manchuria) where he taught aikibudo (an early name for aikido) to the Kanton army and the Imperial Household Agency. In 1938 he became an assistant professor at Kenkoku University in Manchukuo. He went on to be awarded the first 8th dan in aikido (1942) and an 8th dan in judo. After returning from a three year internment by the Soviet Union, he taught both judo and aikido for many years at Waseda University. It was there that he formulated and expanded his theories concerning both kata based training methods and a particular form of free-style fighting which would put him at odds with much, but not all, of the aikido world.
In 1974 he founded the Japan Aikido Association (JAA) from an earlier organization of the same name to promote his theories. He called his style Shodokan Aikido and a honbu dojo, dedicated solely for the study of aikido, had been built in 1967 in Osaka. The current head of the dojo and chief instructor of the JAA is Tetsuro Nariyama.