Kiyomitsu Samuel Nagasawa is a Japanese kickboxer, currently competing in the lightweight division of K-1 where he is the reigning K-1 Lightweight champion.
As of September 2026 he was the No. 2 ranked -64kg kickboxer in the world by Beyond Kickboxing
Career Shin Nihon Kickboxing Association Nagasawa made his professional debut on April 8, 2012, at SNKA "Superkick" against Koichi Ashima. He won the fight by unanimous decision.
For his second professional fight Nagasawa faced Choji Horiguchi at SNKA SLEDGE HAMMER IV on June 10, 2012. The fight ended in a draw.
On November 24, 2013, Nagasawa faced Daiju Takahira at SNKA Kick Insist III. He won the fight by first round knockout.
Nagasawa defeated Lee Jin Fan by unanimous decision at the SNKA Super Kick Boxing event on April 6, 2014.
On January 11, 2015, Nagasawa faced Naoya Fukuda at SNKA WINNERS 2015 1st. He won the fight by unanimous decision.
On March 15, 2015, Nagasawa challenged Katsuji at SNKA MAGNUM 37 for the vacant SNKA Lightweight title. He lost the fight by third-round technical knockout.
On May 17, 2015, Nagasawa faced Kyohei at SNKA WINNERS 2015 2nd. He lost the fight by majority decision.
On May 15, 2016, Nagasawa faced Naoto at SNKA WINNERS 2016 2nd. The fight ended in a split draw.
Nagasawa challenged Katsuji at SNKA MAGNUM 41 for his SNKA Lightweight title on July 3, 2016. He lost the fight by unanimous decision.
On November 6, 2016, Nagasawa faced Takuma at SNKA Kick Insist 6. He won the fight by majority decision.
On May 14, 2017, Nagasawa faced Monkongdet Sit-Ubon at SNKA WINNERS 2017 2nd. He won the fight by decision.
On November 19, 2017, Nagasawa faced Taimu Saenchaigym at SNKA Kick Insist 7. He won the fight by majority decision.
On January 7, 2018, Nagasawa faced Yodphet JSK at SNKA WINNERS 2018 1st. He won the fight by unanimous decision.
Japan Kickboxing Association / WBC Muay Thai
On June 12, 2019, Nagasawa faced Shunsuke Miyabi at the Suk Wan Kingthong Go to the Raja event for the vacant Suk Wan Kingthong Lightweight title. He lost the fight by unanimous decision.
On January 5, 2020, Nagasawa faced Konosuke at JKA KICK ORIGIN 2010 1st for the inaugural JKA Lightweight title. He won the fight by third-round knockout.
On September 12, 2020, Nagasawa faced Shoya Suzuki at NJKF 2020 3rd for the vacant WBC Muay Thai Japan Lightweight title. He won the fight by unanimous decision.
On November 22, 2020, Nagasawa lost by unanimous decision to Sila Y'zd at JKA Kick Insist 10.
Morii faced Nagasawa Samuel Kiyomitsu at NO KICK NO LIFE ~Shin Shou~ Ungaisouten on February 24, 2021. He won the fight by a majority decision, with scores of 30–28, 29–29 and 30–29.
On February 12, 2022, Nagasawa successfully defended his WBC Muay Thai Japan Lightweight title against Kenta Yamada, defeating him by unanimous decision at NJKF 2022 1st.
On March 20, 2022, Nagasawa faced Paranrak FellowGym at JKA Kick Insist 12. He won the fight by unanimous decision.
On July 17, 2022, Nagasawa faced Kongdet Por.Pajansee at JKA Kick Insist 13 for the vacant WMO International Lightweight title. He won the fight by unanimous decision.
Nagasawa faced Isannua Chotbangsaen at RWS Japan on February 12, 2024. He lost the fight by unanimous decision.
Krush / K-1 Nagasawa faced Yuzuki Satomi at Krush 164 on August 18, 2024. He lost the fight by a first-round knockout.
On November 16, 2024, Nagasawa faced Shuji Kawarada at Krush 167. He won the fight by unanimous decision.
On February 24, 2025, Nagasawa enterd an 8-man tournament at Krush 171. In the quarterfinals he lost by unanimous decision to Haru Furumiya.
Nagasawa defeated Kuto Ueno by extension round unanimous decision on September 7, 2025, at K-1 World MAX 2025 - World Tournament Opening Round.
On February 8, 2026, Nagasawa faced Yuma Saikyo at K-1 World GP 2026 - 90kg World Tournament|. He won the fight by first-round knockout with body punches.
On May 31, 2026, Nagasawa faced reigning Krush champion Tatsuya Oiwa at K-1 Revenge. He won the fight by unanimous decision.
On September 12, 2026, Nagasawa challenged Yuzuki Satomi for his K-1 Lightweight (-62.5kg) title at K-1 World MAX 2026 - World Tournament Opening Round. He won the fight by second-round technical knockout after surviving a first-round knockdown.
Titles and accomplishments Muay Thai Japan Kickboxing Association 2020 JKA Lightweight Champion
World Boxing Council 2020 WBC Muay Thai Japan Lightweight Champion One successful title defense
World Muaythai Organization 2022 WMO international Lightweight Champion
Kickboxing K-1 2026 K-1 Lightweight (-62.5kg) Champion
Fight record
|- style="text-align:center; background:#cfc | 2026-09-12|| Win ||align=left| Yuzuki Satomi || K-1 World MAX 2026 - World Tournament Opening Round || Tokyo, Japan || TKO (referee stoppage) ||2|| 1:41 |- ! style=background:white colspan=9 |
|- align="center" bgcolor="#cfc" | 2026-05-31 || Win||align=left| Tatsuya Oiwa || K-1 Revenge|| Tokyo, Japan || Decision (unanimous) || 3 || 3:00
|- align="center" bgcolor="#cfc" | 2026-02-08 || Win ||align=left| Yuma Saikyo || K-1 World GP 2026 - 90kg World Tournament|| Tokyo, Japan || KO (body punches)|| 1 || 1:46
|- style="background:#cfc" | 2025-09-07 || Win ||align=left| Kuto Ueno || K-1 World MAX 2025 - World Tournament Opening Round || Tokyo, Japan || Ext.R Decision (unanimous) || 4 || 3:00
|- style="background:#fbb;" | 2025-07-26|| Loss ||align=left| Tenma Sano || Krush 178 || Tokyo, Japan || Decision (unanimous) || 3 || 3:00
|- style="text-align:center; background:#fbb" | 2025-02-24|| Loss ||align=left| Haru Furumiya|| Krush 171 - Lightweight Grand Prix, Quarterfinals || Tokyo, Japan ||Decision (unanimous)|| 3 || 3:00
|- style="text-align:center; background:#cfc;" | 2024-11-16 || Win ||align=left| Shuji Kawarada || Krush 167 || Tokyo, Japan || Decision (unanimous) || 3 || 3:00
|- style="background:#fbb" | 2024-08-18|| Loss ||align=left| Yuzuki Satomi || Krush 164 || Tokyo, Japan || KO (punches) || 1 ||1:57
|- style="background:#fbb;" | 2024-02-12|| Loss|| align=left| Isannua Chotbangsaen || RWS Japan || Tokyo, Japan|| Decision (unanimous) || 3 ||3:00
|- style="background:#c5d2ea;" | 2023-11-26|| Draw|| align=left| Pinsiam Sor.Amnuaysirichoke || JKA Kick Insist 17 || Tokyo, Japan || Decision (majority) || 3 ||3:00
|- style="background:#cfc;" | 2023-07-16|| Win|| align=left| Kennakorn Dabransarakham || JKA Kick Insist 16 || Tokyo, Japan || TKO (low kicks) || 2 ||2:22
|- style="background:#cfc;" | 2023-03-19|| Win|| align=left| Petchpupan Sor.Saknarin || JKA Kick Insist 15 || Tokyo, Japan || TKO (low kicks) || 2 ||2:22
|- style="background:#cfc;" | 2022-11-20|| Win|| align=left| Khomkaew Sit PorChorWor || JKA Kick Insist 14 || Tokyo, Japan || KO (right cross) || 3 ||1:52
|- style="background:#cfc;" | 2022-07-17|| Win|| align=left| Kongdet Por.Pajansee || JKA Kick Insist 13 || Tokyo, Japan || Decision (unanimous) || 5 ||3:00 |- ! style=background:white colspan=9 |
|- style="background:#cfc;" | 2022-03-20|| Win|| align=left| Paranrak FellowGym || JKA Kick Insist 12 || Tokyo, Japan || Decision (unanimous) || 5 ||3:00
|- style="text-align:center; background:#cfc;" | 2022-02-12|| Win || align=left| Kenta Yamada|| NJKF 2022 1st || Tokyo, Japan || Decision (unanimous) ||5 ||3:00 |- ! style=background:white colspan=9 |
|- style="background:#cfc;" | 2021-11-21|| Win|| align=left| Thongmeechai FellowGym || JKA Kick Insist 11 || Tokyo, Japan || KO (left hook) || 2 ||1:50
|- style="background:#cfc;" | 2021-06-13|| Win|| align=left| Lakchai GTgym || Suk Wan Kingthong: Let’s do our best！|| Tokyo, Japan || Decision (unanimous) ||3 ||3:00
|- style="background:#fbb;" | 2021-02-24 || Loss ||align=left| Yosuke Morii || NO KICK NO LIFE ~Shin Shou~ Ungaisouten || Tokyo, Japan || Decision (majority) || 3||3:00
|- style="background:#fbb;" | 2020-11-22 || Loss ||align=left| Sila Y'zd || JKA Kick Insist 10 || Tokyo, Japan|| Decision (unanimous) || 3||3:00
|- style="background:#cfc;" | 2020-09-12 || Win ||align=left| Shoya Suzuki || NJKF 2020 3rd || Tokyo, Japan || Decision (unanimous) || 5||3:00 |- ! style=background:white colspan=9 |
|- style="background:#cfc;" | 2020-01-05 || Win ||align=left| Konosuke || JKA KICK ORIGIN 2010 1st ||Tokyo, Japan|| TKO (referee stoppage) || 3||1:49 |- ! style=background:white colspan=9 |
|- style="background:#cfc;" | 2019-11-09 || Win ||align=left| Kenjiro Tanahashi || JKA Kick Insist 9 ||Tokyo, Japan || TKO (doctor stoppage) || 3||2:29
|- style="background:#fbb;" | 2019-06-12 || Loss ||align=left| Shunsuke Miyabi || Suk Wan Kingthong Go to the Raja ||Tokyo, Japan || Decision (unanimous) || 5||3:00 |- ! style=background:white colspan=9 |
|- style="background:#cfc;" | 2018-11-11 || Win ||align=left| Mai Lookprabaht || SNKA Kick Insist 8 || Tokyo, Japan|| KO (left hook) || 3||2:10
|- style="background:#cfc;" | 2018-08-23|| Win|| align=left| Jackchai Nor.Naksin || Suk Wan Kingthong || Tokyo, Japan || KO (left hook to the body) ||2 ||
|- style="background:#fbb;" | 2018-05-14|| Loss|| align=left| Masayuki Uchida || SNKA WINNERS 2018 2nd|| Tokyo, Japan || TKO (doctor stoppage) ||3 ||2:40
|- style="background:#fbb;" | 2018-01-07|| Loss|| align=left| Yodphet JSK|| SNKA WINNERS 2018 1st|| Tokyo, Japan || Decision (unanimous) ||3 ||3:00
|- style="background:#cfc;" | 2017-11-19|| Win|| align=left| Taimu Saenchaigym || SNKA Kick Insist 7|| Tokyo, Japan || Decision (majority) ||3 ||3:00
|- style="background:#cfc;" | 2017-08-27|| Win|| align=left| Ken Hasegawa || SNKA WINNERS 2017 3rd|| Tokyo, Japan || Decision (unanimous) ||3 ||3:00
|- style="background:#cfc;" | 2017-05-14|| Win|| align=left| Monkongdet Sit-Ubon || SNKA WINNERS 2017 2nd|| Tokyo, Japan || Decision ||3 ||3:00
|- style="background:#cfc;" | 2016-11-06 || Win ||align=left| Takuma || SNKA Kick Insist 6 || Tokyo, Japan || Decision (majority) || 3||3:00
|- style="background:#fbb;" | 2016-07-03 || Loss ||align=left| Katsuji || SNKA MAGNUM 41 || Tokyo, Japan || Decision (unanimous) || 5||3:00 |- ! style=background:white colspan=9 |
|- style="background:#c5d2ea;" | 2016-05-15|| Draw|| align=left| Naoto || SNKA WINNERS 2016 2nd|| Tokyo, Japan || Decision (split) ||3 ||3:00
|- style="background:#fbb;" | 2015-11-15 || Loss ||align=left| Katsushi Muranaka || SNKA Kick Insist 5 || Tokyo, Japan || KO (high kick)|| 3||2:18
|- style="background:#cfc;" | 2015-07-12|| Win|| align=left| Tadashi Kaneko || SNKA MAGNUM 38|| Tokyo, Japan || KO (straight to the body) ||1 ||1:22
|- style="background:#fbb;" | 2015-05-17 || Loss ||align=left| Kyohei || SNKA WINNERS 2015 2nd || Tokyo, Japan || Decision (majority)|| 3||3:00
|- style="background:#fbb;" | 2015-03-15 || Loss ||align=left| Katsuji || SNKA MAGNUM 37 || Tokyo, Japan || TKO (corner stoppage)|| 3||1:56 |- ! style=background:white colspan=9 |
|- style="background:#cfc;" | 2015-01-11|| Win|| align=left| Naoya Fukuda || SNKA WINNERS 2015 1st|| Tokyo, Japan || Decision (unanimous) ||3 ||3:00
|- style="background:#cfc;" | 2014-11-16|| Win|| align=left| Ryota || SNKA Kick Insist 4|| Tokyo, Japan || Decision (unanimous) ||3 ||3:00
|- style="background:#cfc;" | 2014-07-20|| Win|| align=left| Haruki || SNKA MAGNUM 35|| Tokyo, Japan || Decision (unanimous) ||3 ||3:00
|- style="background:#cfc;" | 2014-04-06|| Win|| align=left| Lee Jin Fan || SNKA Super Kick Boxing|| Chiba, Japan || Decision (unanimous) ||3 ||3:00
|- style="text-align:center; background:#cfc;" | 2013-11-24 || Win ||align=left| Daiju Takahira || SNKA Kick Insist III || Tokyo, Japan || KO || 1 || 1:10
|- style="text-align:center; background:#cfc;" | 2013-09-16 || Win ||align=left| Kazuki || SNKA TITANS NEOS XIV || Tokyo, Japan || KO || 2 || 1:39
|- style="background:#c5d2ea;" | 2013-04-07|| Draw|| align=left| Fang In Woo || SNKA Super Kick Boxing|| Ichihara, Chiba, Japan || Decision (majority) ||3 ||3:00
|- style="background:#fbb;"