全日本柔道選手権大会
Ōsawa was born March 6, 1926 in Sakura, Chiba Prefecture, Japan. He was educated at Waseda University and later became a judo instructor there. Osawa weighed in at 145lbs but competed against all sizes. Although at times he went as big as 5'6 160lbs. He was highly regarded as a Judo technician, particularly for his ashi-waza and, although a light weight, was considered a favourite to win the All-Japan Judo Championships and defeated the 1948 champion Yasuichi Matsumoto to win the Fukuoka tournament in November 1948. After he retired, he made a trip to Brazil. He was challenged by Helio Gracie, whom had previously been defeated by Kimura. As a coach, he was forced to decline the match. Osawa was a primary author of the book Kodokan Judo: A Guide to Proficiency. Osawa was the head instructor at Waseda University. Osawa is considered to be one of the top technicians in Judo post World War II.