The 29-year-old pop star was at the famous amusement park to perform a private gig, but that didn't stop him from enjoying the various attractions on offer with his friends while also mingling with some of the Disney characters.
In fact, Olly couldn't have sounded more excited to be there.
Yesterday afternoon (22 September) he tweeted: "Am a big kid running around Disneyland at the moment... Space Mountain yes, Cars yes, Californian Screaming yes, so far.."
He also posted a picture of himself getting into the Disney spirit by wearing a pair of personalised Mickey Mouse ears.
Olly captioned the cute snap: "Move over Mickey!! New mouse in town!! Haha loving my new hat!! Lol".
After posing for a picture, the former X Factor contestant continued to wear his ears for most of the day, while also bizarrely walking around the Stateside park barefoot!
He kept his outfit simple, wearing a pair of khaki shorts and a plain T-shirt. Hopefully he put a pair of shoes on before his performance!
At the end of the action-packed day, he finally found a moment to relax - even if he was dressed up as Goofy!
Lying down on a leather sofa, Olly had swapped his Mickey Mouse ears for a large green hat with the name 'Goofy' emblazoned across it and a pair of big cartoon gloves.
He tweeted the funny photo and the caption: "It's been a hard day being GOOFY....."
Olly is currently enjoying a flourishing music career in the US, after quitting his role as a host on ITV2's The Xtra Factor.
And now that he is no longer part of the show, the cheeky ex-presenter has admitted that he won't be tuning in because he can't stand the thought of co-host Caroline Flack being on TV alongside someone else.
Earlier this month he said: "I'm going to be too jealous to see a new guy stood next to her."
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