Seina Nakajima (Nagano, JPN) lost 7-6 to Satsuki Fujisawa (Kitami, JPN) in the Final of the Japan National Championship, held February 9 - 16, 2020 at the Karuizawa Ice Park in Karuizawa, Japan. To advance to the championship game, Nakajima won 10-4 over Sayaka Yoshimura (Sapporo, JPN) in the semifinals of the 2020 Japan National Championship in Karuizawa, Japan, Japan;
 
Nakajima finished 8-0 in the 9-team qualifying round. . In their opening game, Nakajima defeated Shinobu Aota (Aomori, JPN) 8-1, then won 14-3 against Yuki Shibuto (Hiroshima, JPN) and 8-5 against Yumiko Kashiwagi (Karuizawa, JPN). Nakajima won 8-1 against Yoshimura, then won 11-0 against Shiori Fujisawa (Karuizawa, JPN) and 11-4 against Honoka Sasaki (Sapporo, JPN). Nakajima won 8-4 against Tori Koana (Yamanashi, JPN), then won 8-7 against Fujisawa in their final qualifying round match.
 
With their runner-up finish at the Japan National Championship, Nakajima take home 32.003 world rankings points. Nakajima move up 4 spots after posting a net gain of 24.972 points improving upon their best 8 results so far this season, ranking 21st overall with 167.910 total points on the World Ranking Standings. Nakajima ranks 21st overall on the Year-to-Date rankings with 167.910 points earned so far this season.