China's Shandong Airlines said it has agreed to buy 50 737 passenger airplanes worth $4.6 billion from US manufacturer Boeing.
The company "signed an agreement with Boeing on April 21 to purchase 50 Boeing 737 planes", it said in a statement dated Monday.
The order includes the purchase of 16 Boeing 737-800s and 34 Boeing 737MAX models, the statement said, adding that the base price of the total order was about $4.6 billion.
Shandong Airlines, based in eastern China, will receive the aircraft in batches between 2016 and 2020, the statement said.
Shandong Airlines aims to increase its fleet to more than 140 by the end of 2020, nearly doubling its total stock of planes, China's official Xinhua news agency cited a company official as saying late Monday.
The airline already operates 67 Boeing 737 planes, it said.
Shandong Airlines, which is listed on the Shenzhen stock exchange, was up 2.19 percent on Tuesday morning after the news.
Fierce rivals Airbus and Boeing have locked horns in a battle for lucrative orders in China, which is seeing a rapidly expanding domestic carrier sector.
While slow growth in Western economies is hitting the aviation industry, Asian countries are booming with an emerging middle class keen to take to the air.
Boeing in 2012 overtook Airbus for the first time in 10 years as the world's biggest plane maker in terms of aircraft delivered.
In the next two decades, Chinese passenger travel is forecast to increase five-fold, according to industry estimates.