Mohammad Mosaddeq (June 16, 1882 – March 5, 1967) is an Iranian politician who serves as the 35th Prime Minister of Iran, holding office from 1951 until 1953, when his government is overthrown in the 1953 Iranian coup d'état orchestrated by the United States' Central Intelligence Agency and the United Kingdom's MI6.

An author, administrator, lawyer and prominent parliamentarian, his administration introduces a range of social and political measures such as social security, land reforms and higher taxes including the introduction of taxation of the rent on land.

His government's most significant policy, however, is the nationalization of the Iranian oil industry, which had been built by the British on Persian lands since 1913 through the Anglo-Persian Oil Company (APOC/AIOC), later known as British Petroleum (BP).

Many Iranians regard Mosaddegh as the leading champion of secular democracy and resistance to foreign domination in Iran's modern history.

Following an initial, failed coup attempt by the CIA/MI6-backed General Fazlollah Zahedi, Mosaddegh resigns four days later on August 19, 1953, with Zahedi succeeding him as prime minister.

While the coup is at times referred to in the West as Operation Ajax after its CIA cryptonym, in Iran it is referred to as the 28 Mordad 1332 Coup d'état, after its date on the Iranian calendar.

Mosaddegh is imprisoned for three years, then put under house arrest until his death and is buried in his own home so as to prevent a political furor.

In 2013, the U.S. government formally acknowledges the U.S. role in the coup, as a part of its foreign policy initiatives.