Diaz,, Ruben was born on April 26, 1973 in Bronx, New York, United States. Son of Rubén Díaz and Didionilda Vega.
Attended, Laguardia Community College. Bachelor in Political Theory, City University of New York Lehman College.
Supervisor New York City Council, 1992, Democratic district leader, 1994—1996. Member New York State Assembly from District 75, 1997—2002, New York State Assembly from District 85, 2003—2009, chair Assembly Committee on Election Law, 2009. Borough president Bronx, New York, since 2009.
Married Hilda Yvette Gerena. Children: Ruben III, Ryan Isaiah.