Michael John Moorcock is an English writer, primarily known for his work in the genres of science fiction and fantasy. He has also published several literary novels. Moorcock is best known for his novels about the character Elric of Melniboné, which were a seminal influence on the field of fantasy during the 1960s and 1970s.

As the editor of the British science fiction magazine New Worlds, from May 1964 until March 1971 and then again from 1976 to 1996, Moorcock played a key role in the development of the science fiction "New Wave" in the UK and indirectly in the United States, leading to the advent of cyberpunk. His publication of Bug Jack Barron (1969) by Norman Spinrad as a serial novel was notorious; in Parliament, some British MPs condemned the Arts Council of Great Britain for funding the magazine.

In addition to writing, Moorcock is a musician and has contributed to music acts including Hawkwind, Blue Öyster Cult, Robert Calvert, and Spirits Burning, as well as leading his own project, Michael Moorcock & The Deep Fix.

In 2008, The Times included Moorcock in its list of "The 50 greatest British writers since 1945".