A United Nations Secretary-General selection was held in 2006 to succeed Kofi Annan, whose second term as Secretary-General of the United Nations ran until 31 December 2006. Seven candidates were officially nominated for the position.

The United Nations Security Council conducted a series of unofficial straw polls between 24 July and 2 October. South Korean Foreign Minister Ban Ki-moon led the polls from the start, emerging as the only candidate with the support of all five veto-wielding permanent members of the Security Council (P5). After the final straw poll, all of the other candidates withdrew. The Security Council conducted a formal vote on 9 October and forwarded its choice to the General Assembly, which elected Ban on 13 October.

The United Nations Charter provides for the Secretary-General to be appointed by the General Assembly upon the nomination of the Security Council. Therefore, the selection is subject to the veto of any of the five permanent members of the Security Council.

The Charter's minimal language has since been supplemented by other procedural rules and accepted practices. There is an unofficial term limit of two full terms, disqualifying Kofi Annan from re-selection. A system of regional rotation is in place to select a new Secretary-General after the previous one has served two terms. The ability of a candidate to converse in both English and French is also considered an advantage, although this is not always enforced.

The Security Council conducts a series of straw polls in private to gauge the level of support for each candidate. When a candidate appears to be winning, another straw poll is taken to reveal vetoes. The candidate with no vetoes, at least 9 votes, and more votes than the other candidates is considered to be the most likely choice. The Security Council then takes a formal public vote to announce its choice, and the General Assembly votes to accept the Security Council's recommendation.

When the race to succeed Annan began in 2006, it was widely expected that the successful candidate would be Asian, as there had not been a Secretary-General from Asia since 1971. A number of Security Council members (including China, which has a veto) indicated they would only support an Asian candidate.

Noting that all Secretaries-General to date have been men, Equality Now launched a campaign for the election of a female Secretary-General, and identified a ‘sampling’ of 18 qualified women, including Vaira Vīķe-Freiberga, Louise Arbour, Gro Harlem Brundtland, and Tarja Halonen. Equality Now also noted that there are many qualified Asian women, including Aung San Suu Kyi from Burma, Sadako Ogata from Japan, Nafis Sadik from Pakistan, Anson Chan from Hong Kong, and Leticia Shahani from the Philippines. The idea of a female Secretary-General received some support, (including from Kofi Annan and US Ambassador to the UN John Bolton), but no Asian women were nominated.

Seven candidates were officially nominated for the position: