The 26-year-old will fight in Britain for the first time in two years in Sheffield against the Mexican, and insisted that the contest will be intriguing for spectators.
Khan said: "It's been two years since I last fought in the United Kingdom (against Paul McCloskey in Manchester) and I can't wait to get in the ring in front of my fans.
"Julio Diaz is a former world champion and a very dangerous opponent who is coming off an impressive performance in his last fight. I know he will be coming with guns blazing and I'm ready for whatever he has to throw at me. With my speed and boxing skills, and his power and experience, it makes for a really exciting match-up.
"He may have other ideas but I'm adamant that my return to the British shores is going to be a very successful one."
Khan's previous four fights have taken place in the US.