Fantasy Masterworks is a series of British paperbacks by Millennium (an imprint of Victor Gollancz). It is intended to comprise "some of the greatest, most original, and most influential fantasy ever written" and to contain "the books which, along with Tolkien, Peake and others, shaped modern fantasy." as claimed by its publisher.

It has a companion series in the SF Masterworks line. A separate Future Classics line has also started featuring eight science fiction novels from the last few decades.

The books were numbered only through No. 50; in the 2013 reboot of the series, the books are unnumbered, have a uniform look, and feature introductions by well-known writers and critics.

* Also published in the Fantasy Masterworks numbered series.