Akari Inoue won the women's over-78 kg division on Saturday, the first day of the Kodokan Cup, one of the qualifying events for next year's judo world championships.
The 20-year-old Inoue, the Universiade unlimited weight class champion, defeated last year's runner-up, Akira Sone by ippon at Chiba Port Arena outside Tokyo.
Saki Nizoe won her second straight 70-kg championship, while Shori Hamada won the 78-kg crown after winning it for the first time two years ago.
Another Universiade champ, Arata Tatsukawa, defended his men's 73-kg championship after defeating Masashi Ebinuma, a two-time Olympian in the 66-kg division, in the semifinals.
Seiya Miyanohara captured his first 60-kg title, while Joshiro Maruyama won his second championship at 66 kg. Takeshi Sasaki claimed his first 81-kg title.