If Mohegan Gaming is awarded the license to build the property, it will be the first integrated resort and casino in the country.
The plans include a luxury hotel, entertainment venues, a convention centre and casino.
The operator estimates the project will create more than 7,000 jobs in the region during and after construction, while international tourism in the area is expected to increase by at least 10%.
Hard Rock Entertainment is the only other bidder for the right to operate a casino in the €8bn ($8.78bn) Hellinikon project.
The winning operator will receive a 30-year gaming license from the Hellenic Gaming Commission to build and operate a casino property on the site of the vacant Ellinikon International Airport.
Mario Kontomerkos, Mohegan Gaming Chairman and CEO, said: "We understood Inspire Athens was meant to symbolise more than an integrated resort.
"It is our hope Inspire Athens would be the catalyst that sparks the entire development of the Hellinikon area into the coveted Athenian Riviera, forever redefining the modern identity of Greece."