The gown cut off at the knee and the Duchess chose to leave her legs bare.
On the front of the dress was subtle detailing of two white buttons.
The mother-of-three carried an envelope clutch bag.
She kept her jewellery to a minimum.
Kate completed the look with a pair of nude closed toe high heel shoes.
She wore her long dark hair down and styled into a bouncy blow-dry.
The royal was spotted entering the event with Prince William, Camilla, Duchess of Cornwall, Prince Charles and Queen Elizabeth II.
This was not the first appearance from Kate today as the G7 officially kicked off.
The Duchess of Cambridge was seen earlier today with the US First Lady Jill Biden.
The two women visited a primary school in Hayle, Cornwall.
Kate stunned wearing a bold pink dress by Alexander McQueen, one of Kate’s most worn designers.
The midi dress was pulled in at the waist by a matching pink chunky belt.
It had a high neckline and capped sleeves and the royal wore it with a pair of nude high heel shoes.