The Wollemi pines, in the Blue Mountains World Heritage Area, has become the first site in the state to be declared an asset of intergenerational significance.
The declaration is a legally recognised mechanism to bolster existing measures that protect the species for future generations.
The premier, Gladys Berejiklian, said the declaration recognises the extraordinary global significance of the Wollemi pines.
"This declaration enables us to take existing protections up another notch and set specific legislative requirements including a dedicated fire management strategy to secure the survival of the species for generations to come," Ms Berejiklian said.
"Prior to their discovery in 1994, Wollemi pines were only known to us in fossil records with fossil evidence pointing to the species' existence up to 90 million years ago."
Just over 12 months ago, teams from the RFS and National Parks undertook an extensive operation to protect the Wollemis from extinction when the secret site came under threat from the devastating summer bushfires.
Environment Minister Matt Kean said the site is the first to be declared under new provisions in the National Parks and Wildlife Act that will enhance conservation for the most precious and rare jewels in our national parks crown.
"The Wollemi pines are often described as a living fossil, having been around when dinosaurs roamed the Earth," Mr Kean said.
"Despite the incredible efforts by the NPWS and RFS teams last summer, several hundred juvenile trees in the protected site were impacted and are yet to resprout. That's why we need to act now to put long-term protections in place."
The Nature Conservation Council welcomed the decision. Acting chief executive, Jacqui Mumford, said: "The Wollemi pine is a critically endangered iconic species that must be conserved at all costs. We hope this new designation will also be applied to the other 100 species in NSW that are listed as critically endangered."
The Wollemi move came as the premier also announced $257 million funding over three years for national parks.
Environment Minister Matt Kean said almost $41 million has been earmarked for the Mountains region. This includes a new path, upgraded seating and amenities at Evans Lookout in Blackheath,
"Work is also underway along the southern escarpment with NPWS crews and specialist contractors currently constructing the Grand Cliff Top Walk - a $10 million world-class track that will take people along the valley top, waterfalls and cliff edge lookouts between Wentworth Falls and Katoomba and provide an exceptional experience of this World Heritage Area."