The British royal explained that he was so excited the evening before the highly-anticipated royal wedding ceremony that he was unable to drift off.
In new documentary Elizabeth: Queen, Wife, Mother, he said: "I hadn't slept at all that night because obviously all the crowds were on The Mall. They were singing and cheering all night long.
"So, the excitement of that, the nervousness of me, and everyone singing meant I slept for about half an hour. So when I did get up in the morning, I can say that I had prepared myself totally by that point."
The couple got married in April last year in a televised ceremony that garnered a huge audience around the world.
The prince admitted that he struggled after the ceremony, as he was concerned that he would fall due to spurs attached to his boots.
He said: "The hardest thing was trying to walk down the stairs with my spurs on, sideways. I had visions of myself and my brother Harry colliding and crashing down the stairs together."
Prince William and the Duchess of Cambridge recently attended the Audi Polo Challenge in Ascot together.
Elizabeth: Queen, Wife, Mother airs in the UK on ITV1 on Friday, June 1.