His biggest role would land in 1975. George Lucas hired Harrison to build some cabinets at his home. Lucas was casting people for his new project, a science fiction film called The Star Wars. He asked Harrison to read Han Solo lines to other actors, but he didn't plan to cast him for the role. ("because he wanted new faces, and apparently I was an old face...even then"). However, Lucas soon noticed Harrison was the best choice for the part of Han Solo.

Star Wars became the mega-success of which finally made Harrison Ford a household name and gave him the chance to do the next two Star Wars sequels, The Empire Strikes Back and Return of the Jedi, as well The Star Wars Holiday Special. He followed that with a series of box-office duds, including Force 10 From Navarone, Hanover Street (both in 1978), and The Frisco Kid (1979), and had cameos in Coppola's Apocalypse Now, and More American Graffiti (both in 1979).