Tugstsogt Nyambayar (; born 23 June 1992) is a Mongolian professional boxer who held the IBO featherweight title in 2019 and challenged for the WBC featherweight title in 2020. As an amateur, he won silver medals at the 2009 World Championships and 2012 London Olympics. As of June 2020, he is ranked as the world's seventh best active featherweight by "The Ring" and the Transnational Boxing Rankings Board.