George Lucas directed four Star Wars films: the original Star Wars, later titled A New Hope, plus The Phantom Menace, Attack of the Clones, and Revenge of the Sith. These are the first film and all three entries in the prequel trilogy.
Lucas directed Star Wars in 1977, creating the space-opera universe that became a global cultural phenomenon. He did not direct The Empire Strikes Back or Return of the Jedi; those films were directed by Irvin Kershner and Richard Marquand. Lucas remained deeply involved as creator, writer, and producer, which can make his directing total seem higher.
He returned to the director’s chair for The Phantom Menace in 1999, his first feature directing credit since 1977. He then directed the next two prequels, completing Anakin Skywalker’s tragic transformation into Darth Vader. The number is therefore four, not six: all six films in the original pre-Disney saga were not directed by Lucas.