Lễ nhậm chức lần thứ hai của Lyndon B. Johnson

The second inauguration of Lyndon B. Johnson as president of the United States was held on Wednesday, January 20, 1965, at the East Portico of the United States Capitol in Washington, D.C. This was the 45th inauguration and marked the second and only full term of Lyndon B. Johnson as president and the only term of Hubert Humphrey as vice president. Chief Justice Earl Warren administered the oath of office. Lady Bird Johnson founded the tradition of incoming first ladies participating in the ceremony by holding the sworn in president's Bible. Vice President Humphrey was sworn in by John W. McCormack, the speaker of the House of Representatives. This was the first inauguration when the president rode in a bulletproof limousine.

An estimated 1.2 million attended the inauguration, the third largest crowd for any event ever held at the National Mall, behind the inaugurations of Truman in 1949 and Obama in 2009. This was the last time an inauguration was covered by newsreels.

Weather conditions for 12 noon at Washington National Airport, located 3.1 miles from the ceremony, were: 37 °F (3 °C), wind 9 mph, and no precipitation.