Prince Harry will kick off the event with a speech delivered from the Sydney Opera House on the fifth day of the historic 16-day tour of Oceania by the royal couple.
The competition was created by the Duke of Sussex, where wounded, wounded or sick war veterans participate in a variety of sports.
Events include wheelchair basketball, seated volleyball and indoor rowing.
The multi-sport event begins on Saturday and will last 7 days, before the end of Saturday 27.
The games will start at 3am BST.
Follow below to get live updates on everything that happens on day five of the Royal tour (every time on BST).
03:30 update: Harry and Meghan applaud the wounded soldiers competing in the 2018 Invictus Games.
The couple stopped to talk to the competitors participating in the Jaguar Land Rover Driving Challenge.
The newlyweds will award the medals to the winners of the event.
Australia and France are fighting for gold in the final.
03:00 update: Harry and Meghan arrived at Cockatoo Island for the opening ceremony of the Invictus Games
02:55 update: The Duke and the Duchess are being transported by boat to the island of Cockatoo.
You will see the Jaguar Land Rover Driving Challenge and you will see which country gets the first gold medal of the competition.
02:45 update: Kensington Palace paid tribute to the fallen soldiers of Australia after the visit of Prince Harry and Meghan Markle to the Anzac Memorial in Hyde Park
00:55 update: Duke and Duchess will attend the Jaguar Land Rover Management Challenge of Invictus Games Sydney 2018
The event will be held on Cockatoo Island at lunchtime (local time).
Competitors from 12 countries will participate in three challenges that include a water obstacle course and two driving challenges.
One will involve cones to test the driver's ability on the car.
00:50 update: Prince Harry and Meghan laid a wreath at the memorial before leaving Hyde Park
The Governor of New South Wales, retired General David Hurley, Prime Minister Scott Morrison and New South Wales Premier Gladys Berejiklian attended the event.
00:45 update: Duke and Duchess receive an indigenous welcome at the Centenary Memorial extension ceremony
Harry and Meghan shook hands with the men during the visit.
He played a didgeridoo.
00:01 update: Meghan Markle and Prince Harry have arrived for the opening of the improved Anzac Memorial in Sydney's Hyde Park
The Duke of Sussex wears a military uniform, while the Duchess wears a black turtleneck dress with buttons on the front and hat.
Friday, September 19
23:55 update: Prince Harry and Meghan Markle have they left Admiralty House where they stay during their visit to Sydney
The royal couple has already left the Admiralty House. Y are Heading towards the Anzac Memorial in Sydney for his first engagement.