John Samuelsen (born 1967 or 1968) is an American labor union leader.
Born in Brooklyn, Samuelsen became a track worker on the New York Subway and joined the Transport Workers Union of America (TWU) in 1993. In 2009, he was elected president of the union's Local 100, in which role he negotiated an agreement covering 38,000 workers.
Samuelsen was elected as president of the TWU in 2017, its youngest leader since Mike Quill. He credited Quill's career as an inspiration. He was also elected as a vice-president of the AFL-CIO.