Biden was the son of Joe Biden and his first wife, Neilia Hunter. His mother and sister were killed in a car accident in 1972.
"The entire Biden family is saddened beyond words," Vice President Biden said in a statement, as reported by the Washington Post. "We know that Beau's spirit will live on in all of us--especially through his brave wife, Hallie, and two remarkable children, Natalie and Hunter."
Biden graduated from the University of Pennsylvania and got his law degree from Syracuse University in 1994. He served as the attorney general of Delaware from 2007 to January 2015. He did not seek reelection because he was planning to run for governor of the state in 2016.
Biden suffered a stroke in 2010 and was diagnosed with brain cancer in 2013.
President Obama also issued a statement about his passing, saying: "Beau took after Joe. He studied the law, like his dad, even choosing the same law school. He chased a life of public service, like his dad, serving in Iraq and as Delaware's Attorney General. Like his dad, Beau was a good, big-hearted, devoutly Catholic and deeply faithful man, who made a difference in the lives of all he touched - and he lives on in their hearts."
In addition to his father and stepmother, Biden is survived by his wife and their two children.