Air China said it would purchase 20 Boeing 737-800 aircraft, two Boeing 747-8 aircraft, one Boeing 777-300ER aircraft and eight Boeing 777 cargo planes.
The total value of the deal is $5.2 billion at current Boeing list prices.
"The Boeing Company has granted to the Company significant price concessions with regard to the Boeing Aircraft," Air China said in a statement.
The deal is subject to Chinese government approval.
Boeing spokesman Jim Proulx said Boeing would announce the order upon government approval.
"We look forward to working with Air China, a long-time valued customer, to obtain approval," he said in an email to AFP.
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