Kenji Watanabe

was a Japanese breaststroke swimmer. He represented his native country in three consecutive Summer Olympics, starting in 1984. His best Olympic result was the 7th place (2:14.70) in the Men's 200m Breaststroke event at the 1992 Summer Olympics in Barcelona, Spain. He was the grandson of Hisakichi Toyoda, who won a gold medal in the 4 × 200 m freestyle in the 1932 Summer Olympics.

At the 1986 Asian Games in Seoul, Watanabe won the gold medal in the 200m breaststroke and the bronze medal in the 100m breaststroke.

Watanabe again won gold in the 200m breaststroke at the 1990 Asian Games in Beijing. He also won silver medals in the 100m breaststroke and the 4 × 100 m medley relay.

Watanabe died at his home on September 18, 2017 at 48 years old.