Julian Emanuel Zelizer (born 1969) is an American professor of political history and author at Princeton University. Zelizer focuses on the second half of the twentieth century and the twenty-first century, and has authored or co-authored several books about American political history.

Raised in Metuchen, New Jersey, Zelizer was educated at Metuchen High School, a comprehensive public high school, followed by Brandeis University. He obtained a PhD in history from Johns Hopkins University.

Zelizer has contributed to CNN.com and The Atlantic. He is a regular commentator on news programs and has appeared in several documentary films. He penned the introduction to a 2016 edition of the Kerner report. He is the Malcolm Stevenson Forbes Professor of History and Public Policy.

He has twice won the D. B. Hardeman Prize, for Taxing America: Wilbur D. Mills, Congress, and the State, 1945–1975 and The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society.

Fault Lines: A History of the United States Since 1974, co-authored with Kevin M. Kruse, received wide critical acclaim.

Zelizer's book, Burning Down the House: Newt Gingrich, the Fall of a Speaker, and the Rise of the New Republican Party, was called "insightful" by The New York Times, which also recognized it as one of the "100 Notable Books of 2020". The Washington Post wrote that it was "engaging" and "timely".

In 2025, Zelizer began a Substack publication online that is entitled, The Long View, and is intended to provide a historical perspective to breaking news that enables free and paid subscribers to gain a better understanding of current events.

Zelizer is the son of the Princeton sociologist Viviana Zelizer and Gerald L. Zelizer, a notable Metuchen rabbi. In 1996, he married Nora Kay Moran at Congregation Adas Israel in Washington, D.C., presided over by his father. In 2012, he married fellow historian Meg Jacobs at the Synagogue for the Arts in New York City, again presided over by his father.