The monarchy of Papua New Guinea is a system of government in which a hereditary monarch is the sovereign and head of state of Papua New Guinea. Queen Elizabeth II was the first monarch of the country - from 16 September 1975 when Papua New Guinea gained independence, until the Queen's death on 9 September 2022 (due to a time zone difference, it was 9 September there while it was 8 September in the United Kingdom).
Although the person of the sovereign was equally shared with fifteen other independent countries within the Commonwealth of Nations, each country's monarchy is separate and legally distinct. As a result, Elizabeth II was officially titled the Queen of Papua New Guinea and, in this capacity, she, her consort, and other members of the Royal Family undertook public and private functions domestically and abroad as representatives of the Papua New Guinean state. However, the Queen was the only member of the Royal Family with any constitutional role. The Queen lived predominantly in the United Kingdom and, while several powers are the sovereign's alone, most of the royal governmental and ceremonial duties in Papua New Guinea were carried out by the Queen's representative, the governor-general.