The Fall of Saigon was the capture of Saigon, the capital of South Vietnam, by the North Vietnamese Army on April 30, 1975. The event marked the end of the Vietnam War and the start of a transition period leading to the formal reunification of Vietnam under communist rule.

North Vietnamese forces under the command of the Senior General Văn Tiến Dũng began their final attack on Saigon, which was commanded by General Nguyen Van Toan on April 29, with a heavy artillery bombardment. By the afternoon of the next day, North Vietnamese troops had occupied the important points within the city and raised their flag over the South Vietnamese presidential palace. South Vietnam capitulated shortly after. The city was renamed Ho Chi Minh City, after communist leader Ho Chi Minh. The fall of the city was preceded by the evacuation of almost all the American civilian and military personnel in Saigon, along with tens of thousands of South Vietnamese civilians associated with the southern regime. The evacuation culminated in Operation Frequent Wind, which was the largest helicopter evacuation in history. In addition to the flight of refugees, the end of the war and institution of new rules by the communists contributed to a decline in the population of the city.

Chaos, unrest, and panic broke out as hysterical South Vietnamese officials and civilians scrambled to leave Saigon. Martial law was declared. American helicopters began evacuating South Vietnamese, U.S., and foreign nationals from various parts of the city and from the U.S. embassy compound. Operation Frequent Wind had been delayed until the last possible moment, because of U.S. Ambassador Graham Martin's belief that Saigon could be held and that a political settlement could be reached.

Schlesinger announced early in the morning of 29 April 1975 the evacuation from Saigon by helicopter of the last U.S. diplomatic, military, and civilian personnel. Frequent Wind was arguably the largest helicopter evacuation in history. It began on 29 April, in an atmosphere of desperation, as hysterical crowds of Vietnamese vied for limited space. Martin pleaded with Washington to dispatch $700 million in emergency aid to bolster the regime and help it mobilize fresh military reserves. But American public opinion had soured on this conflict.

In the United States, South Vietnam was perceived as doomed. President Gerald Ford had given a televised speech on 23 April, declaring an end to the Vietnam War and all U.S. aid. Frequent Wind continued around the clock, as North Vietnamese tanks breached defenses on the outskirts of Saigon. In the early morning hours of 30 April, the last U.S. Marines evacuated the embassy by helicopter, as civilians swamped the perimeter and poured into the grounds. Many of them had been employed by the Americans and were left to their fate.

On 30 April 1975, VPA troops overcame all resistance, quickly capturing key buildings and installations. A tank crashed through the gates of the Independence Palace, and at 11:30 a.m. local time the NLF flag was raised above it. President Duong Van Minh, who had succeeded Huong two days earlier, surrendered.

The Communists had attained their goal, but the cost of victory was high. By war's end, the Vietnamese had been fighting foreign involvement or occupation (primarily by the French, Chinese, Japanese, British, and American governments) for 116 years.