Nafissatou "Nafi" Thiam (born 19 August 1994) is a Belgian athlete specializing in multi-event competition. She was born in Brussels to a Belgian mother and a Senegalese father. As of May 2018, Thiam holds the Belgian record in women's heptathlon and women's Javelin. She won the gold medal in the heptathlon at the 2016 Summer Olympics, 2017 World Championships and the 2018 European Championships. She was voted IAAF World Athlete of the Year in 2017.
Nafi Thiam started participating in athletics when she was seven years old, winning her first national age group titles in 2009, by which time she was already specializing in the heptathlon. Her favorite athlete at the time was Swedish heptathlete Carolina Klüft. Thiam is a member of RFCL Athlétisme, an athletics club operating under the aegis of the Technical and Sports Department of the Royal Football Club de Liège, and is coached by Belgian former decathlete Roger Lespagnard. She studies geography at the University of Liège.