The company from New Zealand purchased the Northern Territory land for A$195m in 2004 and, earlier this year, the Australian Financial Review reported the casino complex could be worth between A$200m and A$250m.
The agreement excludes the Little Mindil property, which is likely to be sold in a separate process.
SkyCity Entertainment Group CEO, Graeme Stephens, said: "I’m really pleased that following a very competitive tender process Delaware North had emerged as the successful bidder.
"They are a highly respected and well-established hospitality and gaming company and I’m very comfortable handing over the business we have built up over the past 14 years to an operator of this calibre."
The deal is now subject to approval from Northern Territory Attorney-General Natasha Fyles.
On how the deal affects future SkyCity plans, Stevens said: "The sale is consistent with our ‘capital lighter” strategy to sell non-core assets and to allocate capital to assets and business which we feel are aligned with our long-term strategic objectives.
"It also allows us to concentrate our Australian activities in Adelaide, which is undergoing a A$330m expansion."
