Two new marine parks will be established off Christmas Island and Cocos (Keeling) Islands in the Indian Ocean.
The federal government confirmed the move after months of consultation with locals and an earlier $5.4 million commitment.
The two areas — which are more than 2,000 kilometres off the coast of Western Australia — are home to many species found nowhere else on Earth.
The Cocos (Keeling) Island's pristine environment is encircled by turquoise lagoons, while Christmas Island is the tip of a 5,000-metre submarine volcano.
Christmas Island has an extraordinary ocean drop-off, which is home to hundreds of fish species, as well as world-class rainforests, which house famous red crabs.
Australia's 'Galapagos Islands'
Minister for Environment Susan Ley said the new marine parks would cover 744,000 square kilometres.
"The region, which is often described as Australia's Galapagos Islands, supports unique underwater reefs and rare aquatic species which act as a natural laboratory, helping us to understand more about the evolution of the oceans," Ms Ley said.
"Today's announcement is a strong reminder of the need to protect our oceans, as these two marine parks join a network of 60 Commonwealth marine parks around Australia, spanning more than 4-million square kilometres — a staggering 45 per cent of Australia's waters."
Inshore sustainable fishing allowed
The waters are critical areas for the spawning of bluefin tuna, which have been a target of illegal international fishermen.
Assistant Minister for Regional Development and Territories Nola Marino said while offshore parts of the park would be placed under the highest level of protection, the community would still be able to sustainably fish inshore.
"The marine parks were co-designed with the local community to ensure that they help maintain their sustainable local food source and way of life, and ensure the parks are a key driver of the local, nature-based tourism industry," she said.
President of the Shire of Cocos (Keeling) Islands, Aindil Minkom, said the marine park would help the community not only protect its pristine reefs, but its culture as well.
"Cocos Island has one of the last reefs, where the corals and reefs are in such a healthy condition, and I guess protecting that would be very beneficial for our community," he said.
"The marine park is important to protect our waters from big industrial fishers."
President of the Christmas Island Malay Association Azmi Yon said the local community had an important connection with the ocean.
"We are surrounded by the ocean that's what we live on, we live from the sea," he said.
"You've got to look after what's around you, rather than pillaging it and destroying it, that's what we don't want."
Cocos Keeling Island deputy shire president Seriwati Iku hoped the marine parks would create more employment for the islands.
