For the occasion, Kate wore a navy blue and white polka dot two-piece ensemble by Alessandra Rich.
The top featuted short sleeves and a ruffled peplum waist, while the skirt flowed loosely down to Kate’s calves.
She paired the ensemble with a simple silver watch and a pair of white stiletto heels.
Prince George matched his mother by wearing a navy blue suit, while Prince William opted for navy trousers, a white shirt, and a beige blazer.
The family will be seated in the royal box as they watch Australian Nick Kyrgios play Novak Djokovic.
On arrival, they were met by a group of military personnel who are working as stewards at the tournament.
Kate explained their role to George, saying: “They look after everybody to make sure the crowds are safe and happy, doing the right thing, in the right seats, making sure the grounds are safe.”
Kate was asked if it was her son’s first time at Wimbledon, prompting her to turn to him and say: “Is this your first time? It is, isn’t it?” to which he replied: “Yes”.
She was asked why her daughter, Princess Charlotte, was not in attendance, and replied: “It’s George’s treat today.”
Kate was also in attendance at Wimbledon on Saturday to watch the women’s singles final, which was won by Elena Rybakina.
For the occasion, Kate wore a bright yellow dress by Roksanda that she had previously worn in Jamaica.
Additional reporting by PA