Kazuo was born in a family of horse racing, with his grandfather Tomio [ja] and father Norihiro being jockeys, as well as his younger brother Takeshi.

[1][2] Kazuo earned his jockey license with the JRA following his graduation from the Horse Racing School in 2011,[3] and raced against his father for the first time in a maiden race held at Nakayama Racecourse on March 5, 2011, where Norihiro finished 3rd while Kazuo 6th.

[4] Kazuo won his first race on April 30th with Laurel Cantata at Niigata Racecourse after 27 starts.

[6] That same year, Kazuo also won the Takarazuka Kinen with Titleholder; which was another race won by his grandfather and father.

[7] This horse racing biographical article is a stub.