- Joseph Robinette Biden Jr. (born November 20, 1942) is the 46th president of the United States of America. He is one of only eight people who served as Vice President before serving as President (in his case, he served under Barack Obama), and only the second person (after Richard Nixon) to have served as a Senator and as Vice President before becoming President. He’s also the oldest person to have been elected President of the United States of America.