The prime minister of Pakistan is the head of government of the Islamic Republic of Pakistan. Executive authority is vested in the prime minister-led and appointed cabinet, with the president of Pakistan serving as the nominal head of executive and state. The prime minister is often the leader of the party or the coalition with a majority in the lower house of the federal parliament, the National Assembly, where he serves as leader of the House. Prime minister holds office by virtue of their ability to command the confidence of the National Assembly. The prime minister is designated as the "chief executive of the Islamic Republic".

Pakistan's prime minister leads the executive branch of the federal government, oversees the state economy, leads the National Assembly, heads the Council of Common Interests as well as the Cabinet, and is charged with leading the National Command Authority over Pakistan's nuclear weapons arsenal. This position places its holder in leadership of the nation and in control over all matters, both internal affairs and foreign policy. The prime minister is elected by the members of the National Assembly and is therefore usually the leader of the majority party in the parliament. The Constitution of Pakistan vests executive powers in the prime minister, who is responsible for appointing the Cabinet as well as running the executive branch, taking and authorizing executive decisions, appointments, and recommendations that require prime ministerial confirmation.

Constitutionally, the prime minister serves as the chief adviser to the president of Pakistan on critical matters; and plays an influential role in appointment in each branch of the military leadership as well as ensuring civilian control of the military through chairman joint chiefs, although this does not necessarily happen in tandem. Prime ministerial powers have significantly grown with a delicate system of check and balance by each branch. The position was absent during the years of 1958–1973, 1977–1985, and 1999–2002 due to imposed martial law. In each of these periods, the military junta led by the president had the powers of the prime minister.

The office of the prime minister was created on immediate effect after the partition and the establishment of Pakistan in 1947; the prime minister existed alongside the governor-general who was the representative of the British monarchy. The first prime minister, Liaquat Ali Khan, exercised central executive powers until his assassination in 1951. The powers slowly began to be reduced as a result of constant intervention by the governor-general. Despite the first set of the Constitution giving central power in 1956, the next six prime ministers were dismissed by the governor-general from 1951 till 1957. The first set of the Constitution had evolved the governor-general into the president of Pakistan whilst declaring the country an "Islamic republic". In 1958, President Iskandar Mirza dismissed the seventh prime minister to impose martial law in a mere two weeks, President Mirza was ousted by army chief General Ayub Khan who had for a brief period held the post of prime minister.

In 1962, the second set of the Constitution completely dissolved the office of prime minister as all powers were transferred to the president of Pakistan. Criticism over the presidency after the presidential election held in 1965 over the centralizing of powers. After the general elections held in 1970, the office was established with Nurul Amin becoming the prime minister who was also the vice-president. Negotiations that fall apart between Zulfikar Ali Bhutto, Mujibur Rehman, and Yahya Khan that prompted to liberation movement in the East Pakistan. With India intervening in East Pakistan and Pakistan conceding defeat to end the war led to the collapse of the presidential system in 1971.

As the comprehensive Constitution reinstated in 1973, the post was reestablished with more central powers as the constitution provided a parliamentary system with President of Pakistan as figurehead. Amid agitation instigated by the right-wing alliance invited the military intervention in 1977 which suspended the post.

The general elections held in 1985 restored the post, with Muhammad Junejo becoming the prime minister. Later that year, the National Assembly passed the controversial eighth amendment to the Constitution, giving the president the power to dismiss the prime minister and the National Assembly without prior consultation. The general elections in 1988 resulted in the Pakistan Peoples Party's Benazir Bhutto becoming the first woman prime minister elected in a Muslim country.

From 1988 to 1993, the power struggle between the prime minister and presidency continued with the president dismissing the National Assembly on three different occasions. At the 1997 elections, the PML(N) secured a two-thirds majority in the Parliament and drafted the XIII and XIV Amendments to reverse the eighth amendment to the Constitution; this allowed Nawaz Sharif to centralize more executive powers. After the draw down of civil-military relations in 1999, Chairman joint chiefs General Pervez Musharraf staged a coup d'état against the PML(N)'s government and held nationwide elections in 2002.