A formal signing of the deal between NPS and Global Infrastructure Partners (GIP) may be made as early as next week, an NPS official has said.
Gatwick was sold by BAA Airports for £1.5bn to GIP, an investment fund controlled by General Electric and Credit Suisse. GIP also owns the London City airport, London's second biggest, which it bought from BAA last year.
NPS is the world's fifth-largest pension fund with about 274tn Korean won (£148bn) in assets. It gained international attention in November when it bought HSBC's European headquarters in Canary Wharf for £773m.
Gatwick Airport, the eighth-busiest in Europe, handles around 34m passengers each year.