Looking a picture of elegance in a pink Alexander McQueen coat dress, Kate Middleton chose to pair the dress with delicate pearl earrings - once owned by Princess Diana - along with a matching pink Juliette Botterill hat.
The royal mum-of-three completed the stunning look with classic nude suede pumps by Gianvito Rossi and a clutch by Loeffler Randall.
It is understood Her Majesty hosts around three garden parties on the grounds of Buckingham Palace each summer.
At each party, approximately 27,000 cups of tea are served along with 20,000 sandwiches and 20,0000 slices of cakes.