The Prime Minister of the Democratic Socialist Republic of Sri Lanka is the head and most senior member of parliament in the cabinet of ministers. It is the second-most powerful position in Sri Lanka's executive branch behind the president, who is the constitutional chief executive. The Cabinet is collectively held accountable to parliament for their policies and actions.

In Sri Lanka, the Cabinet of Ministers is the council of ministers that form the central government of Sri Lanka. The body of senior ministers responsible and answerable to the Parliament of Sri Lanka. The President is a member of the cabinet and its head.