Eliseo Vasquez Medina is a Mexican-American labor union activist and leader, and advocate for immigration reform in the United States. From 1973 to 1978, he was a board member of the United Farm Workers. He is currently secretary-treasurer of the Service Employees International Union. He was previously an international executive vice president, the first Mexican American to serve on the union's executive board. Medina announced his resignation as an SEIU executive vice president effective October 1, 2013.