The couple attended a garden party in honour of Prince Charles' 70th birthday and celebrating his charitable work over the years.
The some 6000 guests were all involved with charities supported by the Prince of Wales.
Meghan nailed her first official royal engagement in the Flavia Silk-Crepe Pencil Dress in soft pink by UK label Goat - a label favoured by her sister-in-law, Kate Middleton. (You can still shop some similar styles here)
The dress, which retails for $590 is of course, sold out, with the company's website crashing almost immediately after the Duchess stepped out in it.
She paired the look with a pair of nude heels, a hat by Philip Treacy and a pink satin clutch.
The newest member of the royal family looked perfectly at ease in her new role, standing side-by-side with Prince Charles and Camilla while Prince Harry made a speech.
“His enthusiasm and energy are truly infectious; it has certainly inspired William and I to get involved in issues we care passionately about and to do whatever we can to make a difference," Harry said.
"In fact, many of the issues William and I now work on are subjects we were introduced to by our father growing up.”
“So, Pa, while I know that you’ve asked that today not be about you, you must forgive me if I don’t listen to you — much like when I was younger — and instead, I ask everyone here to say a huge thank you to you, for your incredible work over nearly 50 years.”
However while Harry was trying to be all serious and honour his father, mother nature had other plans, and the Prince was interrupted by a bee buzzing near his face during the speech. Harry stopped speaking to swat the insect away, saying: "sorry, that bee really got me."
The crowd - and new wife Meghan couldn't help but chuckle!