ONE 166: Qatar was a combat sport event produced by ONE Championship that took place on March 1, 2024, at Lusail Sports Arena in Lusail, Qatar. A ONE Middleweight World Championship bout between current champion Reinier de Ridder (also former ONE Light Heavyweight World Champion) and the ONE Light Heavyweight and Heavyweight Champion Anatoly Malykhin headlined the event.
Anatoliy Malykhin
Reinier De Ridder
Tang Kai
Thanh Le
Joshua Pacio
Jarred Brooks
Amir Aliakbari
Arjan Bhullar
Mehdi Zatout
Zuhayr Al-Qahtani
Vladimir Kuzmin
Zafer Sayik
Cleber Sousa
Osamah Almarwai
Ali Saldoev
Zakaria El Jamari
Shinji Suzuki
Han Zihao
Keito Yamakita
Jeremy Miado