The order is valued at $660 millionat current list prices.
"We look forward to welcoming Kunming Airlines as a 737 MAX 7 launch customer in China and finalizing the deal in the near future", said Boeing Commercial Airplanes President and CEO Ray Conner.
"The addition of more Boeing 737 Max in our portfolio undoubtedly provides the economics, innovative efficiencies, and enhanced passenger experience that our airline customers are looking for in an aircraft".
The 737 MAX 200 is based on the 737 MAX 8, which itself is the re-engined and upgraded variant of the popular Boeing 737.
He added: "With the 737 MAX, we will be able carry our short-haul customers further, in greater comfort, more efficiently and with an even lower environmental impact".
"Donghai Airlines has undergone steady development over the past 10 years since the beginning of our freighter operation in 2006", said Donghai chairman Wong Cho-Bau. "The airplane offers 12 more seats in a two-class interior configuration and more than 20 in a maximum seating configuration, compared to the Next-Generation 737-700". The most lucrative deal came from Shenzhen-based Donhai Airlines, which signed a letter of intent to buy twenty-five 737 Max 8s and five 787-9 Dreamliners in a bid to fulfill a plan to convert its business model from cargo to passenger services.