Thanongsak Simsri
Division: juniorFlyweight
Nationality: Thailand
Hometown: Si Sa Ket, Thailand
Birth Date: 2000-06-17
Height: 5.3 cm
Reach: 64.5 cm
Stance: orthodox
Professional Record
39
Wins
(34 by KO)1
Losses
(1 by KO)0
Draws
40
Total Fights
Biography
Thanongsak Simsri (Thai: ทนงศักดิ์ สิมศรี; born June 17, 2000) is a Thai professional boxer who has held the IBF light-flyweight title since June 2025. Known for his explosive punching power and resilience inside the ring, he is Thailand’s 50th world boxing champion, continuing the country’s long tradition of success in the lighter weight divisions.
Simsri began his combat sports journey in Muay Thai at age 14 before transitioning to professional boxing in 2018. He quickly built an impressive record, earning a title shot against Hiroto Kyoguchi in 2020, though the fight was canceled after the champion tested positive for COVID-19. His first professional defeat came in 2022 against former WBC champion Masamichi Yabuki, but Simsri rebounded strongly, capturing the OPBF light-flyweight title in 2024 with a hard-fought victory over Miel Fajardo.
In June 2025, Simsri achieved his biggest milestone by defeating Christian Araneta to claim the IBF light-flyweight championship in Tokyo. Despite being knocked down early, Simsri rallied with discipline and aggression to secure a split-decision victory. Following the win, he dedicated his triumph to his late grandmother, making the victory deeply personal as well as historic.
Fight History
06/19/25 vs. Cristian Araneta, W-SD, 12/12
02/22/25 vs. Songchai Songklod, W-KO, 3/6
12/15/24 vs. Masataka Taniguchi, W-SD, 12/12
10/05/24 vs. Saravut Rongpig, W-TKO, 2/8
08/04/24 vs. John Paul Gabunilas, W-TKO, 5/12
06/01/24 vs. Assada Rakmit, W-KO, 2/6
04/13/24 vs. Miel Fajardo, W-UD, 12/12
12/16/23 vs. Bordin Chompoo, W-TKO, 1/8
10/22/23 vs. Chiraphan Taosuwan, W-TKO, 2/8
08/06/23 vs. Shota Asami, W-KO, 2/8
06/18/23 vs. Nawamin Klayprayoon, W-TKO, 1/8
04/09/23 vs. Oatsadin Thimthep, W-TKO, 3/6
02/19/23 vs. Weerawat Thongchaichan, W-TKO, 2/8
12/18/22 vs. Chiraphan Taosuwan, W-TKO, 5/8
11/20/22 vs. Sittipon Sangtean, W-TKO, 3/8
09/10/22 vs. Masamichi Yabuki, L-TKO, 7/10
07/24/22 vs. Kris Sriphum, W-TKO, 3/8
05/01/22 vs. Jaturong Yuenyong, W-TKO, 2/8
03/27/22 vs. Benjaphon Phokam, W-TKO, 2/8
02/05/22 vs. Kampanart Valsiripattanachai, W-TKO, 4/6
12/19/21 vs. Natthaphon Buasa, W-TKO, 2/6
10/31/21 vs. Songkran Sosahwat, W-TKO, 1/8
09/26/21 vs. Chanon Sonkham, W-KO, 3/8
07/18/21 vs. Thaweesak Nakham, W-TKO, 3/8
06/06/21 vs. Tongthep Taeyawong, W-RTD, 4/8
03/19/21 vs. Nutthakorn Sungsevee, W-TKO, 3/6
02/06/20 vs. Suriya Puttaluksa, W-TKO, 4/6
12/08/19 vs. Christian Bacolod, W-UD, 8/8
10/12/19 vs. Lerdchai Chaiyawed, W-UD, 6/6
08/31/19 vs. Nattee Thongsingcle, W-KO, 3/8
08/04/19 vs. Mektison Marganti, W-KO, 3/8
06/15/19 vs. Watcharaphon Chaisai, W-TKO, 2/8
05/19/19 vs. Panuwat Yakaret, W-TKO, 1/6
04/21/19 vs. Ricardo Sueno, W-TKO, 1/6
02/05/19 vs. Kermoo, W-KO, 1/8
12/14/18 vs. Phirom Padanprasert, W-KO, 3/6
11/21/18 vs. Manop Audomphanawari, W-TKO, 5/6
09/12/18 vs. Suriya Puttaluksa, W-TKO, 2/4
08/22/18 vs. Prajak Butsree, W-TKO, 2/4
06/20/18 vs. Thanapong Saekoo, W-TKO, 1/4