In a talk at the National Science Museum to mark the start of a new exhibition Prof Hawking also says the Large Hadron Collider may prove the existence of multiple universes.
Known as M-theory Hawking says multiple universes would occur naturally.
"These multiple universes can arise naturally from physical law. Each universe has many possible histories and many possible states at later times, that is, at times like the present, long after their creation.
Most of these states will be quite unlike the universe we observe, and quite unsuitable for the existence of any form of life. Only a very few would allow creatures like us to exist."
Ending his talk, he tells his audience: "So remember to look up at the stars and not down at your feet. Try to make sense of what you see and hold on to that child-like wonder about what makes the universe exist."
Professor Hawking has admitted he was a slacker at university.
As a student of natural science at Oxford University, he once calculated that he did about 1,000 hours of work during his three years at Oxford - an average of an hour a day.
"I'm not proud of this, I'm just describing my attitude at the time, shared by most of my fellow students," Prof Hawking told an event to celebrate the launch of the Science Museum's new "Collider" exhibition.
"Because of my lack of work, I had planned to get through the final exam by doing problems in theoretical physics and avoiding questions that required factual knowledge.
"But I didn't sleep the night before the exam, because of nervous tension, and so I didn't do very well. I was on the borderline between a first and second class degree."
Nonetheless, Hawking was awarded a first and went on to pursue a glittering career in mathematics and cosmology at Cambridge University, where he is now Director of Research at the Department of Applied Mathematics and Theoretical Physics.
Cambridge scientist Professor Stephen Hawking has admitted he was disappointed at the discovery of the Higgs Boson - known as the God Particle.
Hawking is due to give a speech at the National Science Museum today and will say that: "Physics would be far more interesting if it had not been found."
The Higgs boson is theorised to give other particles mass. Had it not been detected last year at the Large Hadron Collider (LHC), the giant atom-smashing machine near Geneva, physicists would have had to reach for a more exotic solution to the mass problem.
Prof Hawking also said the discovery had come at a more personal cost - he lost a $100 bet.
"I had a bet with Gordon Kane of Michigan University that the Higgs particle wouldn't be found," he says. "The Nobel Prize cost me 100 dollars."