Changi Airports International (CAI) has signed a definitive agreement to purchase 29% of Nanjing Lukou International Airport in Jiangsu Province.
Intention to invest US$138 million in the China airport was first announced in January.
"The approach we have taken in this joint venture is to enable our co-operation to be readily expandable to take advantage of these opportunities as and when they arise," said Chow Kok Fong, CEO of Changi Airports International in a statement.
A CAI spokesperson said synergies between the two countries will only be made public when the deal is finalised in mid next year.
Chow said the scope to develop the airport into a major player next to Shanghai was large, particularly for air cargo.