The cheeky toddler, who turns one on Tuesday 22 July, also shows off his newly-acquired walking skills - go George!
The adorable photograph was taken during the Prince's trip to the Sensational Butterflies exhibition at the Natural History Museum in London on July 2.
In it, George can be seen tottering along on a cobbled path, and looking remarkably like his handsome daddy. It's the first time we've seen the future king on his own two feet, without mummy to hold his hand.
Wearing a dark blue collared T-shirt over a pair of striped Petit Bateau dungarees, the dapper son of the Duke and Duchess of Cambridge looks cheek-pinchingly cute.
On his actual birthday, George will have a small party at Kensington Palace.
A palace spokeswoman says: "The family are going to be marking the event privately with close family and friends."
His Royal Highness Prince George of Cambridge was born on 22 July 2013 at 4.24pm at St Mary's Hospital Paddington.
His name was formally announced two days later on July 24, with a Christening following on October 23 at St James's Palace.
He enjoyed his first trip overseas when he accompanied his parents on their official three week tour to New Zealand and Australia.
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