"It is with broken hearts that Hallie, Hunter, Ashley, Jill and I announce the passing of our husband, brother and son, Beau, after he battled brain cancer with the same integrity, courage and strength he demonstrated every day of his life," the vice president said Saturday night.
"The entire Biden family is saddened beyond words. 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," he added.
Beau Biden, who had been considering a run for governor in Delaware, was undergoing treatment at Walter Reed National Military Medical Center.
"Beau's life was defined by service to others. As a young lawyer, he worked to establish the rule of law in war-torn Kosovo. A major in the Delaware National Guard, he was an Iraq War veteran and was awarded the Bronze Star. As Delaware's Attorney General, he fought for the powerless and made it his mission to protect children from abuse," the vice president said.
"More than his professional accomplishments, Beau measured himself as a husband, father, son and brother. His absolute honor made him a role model for our family. Beau embodied my father's saying that a parent knows success when his child turns out better than he did," Biden said.
"In the words of the Biden family: Beau Biden was, quite simply, the finest man any of us have ever known," he said.
President Obama said he and first lady Michelle were also grieving Biden's death.
"Beau took after Joe. He studied the law, like his dad, even choosing the same law school," Obama said. "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.
Beau Biden, the eldest of Joe Biden's sons, sought medical treatment at a Houston cancer center in 2013 after feeling "weak and disoriented." At the time, the vice president and White House refused to discuss his condition, but doctors later said Biden had undergone surgery to remove a small lesion from his brain. He also suffered a mild stroke in 2010.
After the surgery he underwent a normal course of treatment of radiation and chemotherapy, and was given a clean bill of health by his doctor in November 2013.
This spring, however, Biden suffered a recurrence and immediately sought aggressive treatment. He was admitted to Walter Reed earlier this month.
Beau Biden formerly served as attorney general of Delaware. He is survived by his wife Hallie and children Natalie and Hunter.
In 1973, he and his brother Hunter survived a car accident that took the lives of his mother, Neilia, and younger sister Naomi.