In April 2013, it was announced that she would officially become a patron of the museum. One of her most notable appearances was at the Wildlife Photographer of the Year Awards in October, highlighting her love of photography and art that celebrates the beauty and fragility of wildlife. The competition is recognized as the world's leading nature photography event. Catherine wore a custom-made pale blue dress by Jenny Packham, described as a pale jade color on social media.

Her pink clutch bag was designed by Alexander McQueen, and she also wore a new necklace and earrings set by Monica Vinader. During a visit to the museum’s Sensational Butterflies exhibition in July 2017, she mingled with children, highlighting her commitment to educating them about the environment. In October 2019, she opened the Angela Marmont Centre for Biodiversity UK, which aims to promote research on British wildlife and encourage citizen science.

She has interacted with young participants in the museum’s initiatives, demonstrating her focus on inspiring future environmental stewards. Also in July 2017, Catherine and Sir David Attenborough unveiled a new blue whale skeleton. She chose a stunning pale blue dress for the gala, without lavish jewellery or a tiara, but still made a memorable impression. Her dress was by designer Thornton Bregazzi, paired with Prada sandals and a purple clutch.

In October 2018, she visited the Victoria and Albert Museum to preview images for its new Centre for Photography. She wore an off-the-shoulder tweed dress by Erdem, paired with matching velvet heels and a stylish clutch, and wore crystal and pearl hoop earrings by the same designer. Catherine resumed her royal duties last week after taking maternity leave following the birth of Prince Louis in April. It was her first official visit to the museum since becoming its first royal patron in March.

Her involvement with the Natural History Museum highlights her commitment to environmental issues, particularly biodiversity conservation and inspiring children to connect with nature. Her efforts also fit into her broader goals of raising awareness about mental health and the importance of being outdoors. By supporting institutions such as the Natural History Museum, she plays a vital role in encouraging the public to appreciate and protect the natural world for future generations.