The second-in-line to the throne, 36, was joined by Japan’s Deputy Prime Minister Taro Aso at Japan House in Kensington High Street.
The centre, which first opened its doors in June, says on its website it celebrates “the very best of Japanese art, design, gastronomy, innovation, and technology [and] it deepens our appreciation of all that Japan has to offer”.
Prince William spoke of being “deeply honoured” as he recalled his visit to Japan three years ago.
He said the far eastern nation had a “wonderful blend of ancient and modern which so characterises your amazing country”.
What food did Prince William reveal he and Kate love?
During his visit, the Duke of Cambridge was treated to some traditional culinary delights.
He sampled sake wine and salmon sashimi prepared by Akira Shimizu, the chef at the centre’s restaurant Akira.
It was at this point William admitted: “My wife and I love sushi.
“We might have to come down here for lunch when there’s no-one else down.
“Just as long as you don’t get people coming in and saying: ‘I’ll have a burger’.”
The Royal Family are usually advised not to eat seafood when eating out to avoid the risk of food poisoning.
But William was seen to be tucking in as he shared a moment with local children.
However, the visit was not without an awkward faux-pas after the duke made a momentarily slip asking the children if they had eaten “too much Chinese food”.
The embarrassing blunder saw William quickly intervening to retract his verbal mistake, adding “sorry I mean Japanese food”.
The prince also tried a go at a copper beating workshop alongside the young visitors.
The ancient Japanese craft involves making items from single sheets of metal.
What other favourite things did William reveal?
William also let slip during his visit that Kate, Duchess of Cambridge, 36, is more “arty and creative” than him.
The President of the Football Association – and known Aston Villa fan – also proclaimed himself a fan of rugby too, joking: “Holding a rugby ball always gets me excited”.
However, this was most likely a nod to Japan hosting the 2018 Rugby World Cup.