China signed a contract to buy 100 A320 aircraft from European manufacturer Airbus, a spokesman for the firm told AFP, worth $9.7 billion at list prices.
The deal was signed as German Chancellor Angela Merkel on Thursday met Chinese Premier Li Keqiang at the Great Hall of the People in Beijing.
The European Union is China's biggest trading partner and Merkel's trip comes as European leaders jockey for trade and investment deals with the world's second largest economy.
Airbus -- which has an assembly facility in the northern Chinese port of Tianjin -- is engaged in a fierce struggle with Boeing of the US for dominance in the crucial Chinese market.
Thursday's agreement also included the confirmation of 30 options for twin-aisle A330s, which were among a 75-plane deal announced when Li visited Airbus headquarters in the French city of Toulouse in January, the company spokesman told AFP.
During Chinese President Xi Jinping's visit to the US last month, Seattle-based Boeing announced a record purchase of 300 aircraft worth around $38 billion.
China is expected to add 6,330 new aircraft worth $950 billion to its commercial fleet by 2034, Boeing said in August in its annual China Current Market Outlook.
Several major EU countries including Germany, Britain and France are seeking to become hubs for overseas trade of China's yuan currency, and signed up to Beijing's Asian Infrastructure Investment Bank despite US opposition.
Merkel's trip comes between a high profile visit to Britain by China's President Xi Jinping earlier this month, when he stayed at Buckingham Palace in London, and ahead of a trip to China by French President Francois Hollande next week.
Merkel said she was "very happy" to know that Xi had paid such a fruitful visit to Britain, stating: "We welcome competition that is conducive to the promotion of business."
"In Germany, we don't have a Queen," she added, to laughter.
On Friday, the German leader will go with Li to his home province of Anhui, where she will visit a village and a school, echoing President Xi Jinping's escorting of Indian Prime Minister Narendra Modi to his ancestral province of Shaanxi when he visited in May.
"This is the first time since I've become Premier that I've accompanied a foreign leader outside Beijing," Li said.
It "clearly indicates" the good relations between the two leaders and their countries, he added.
Other deals signed in their presence included cooperations between mobile phone manufacturer Nokia and China Mobile, as well as embattled car giant Volkswagen and Chinese bank ICBC.
Deutsche Borse, Germany's stock exchange operator, will also establish a joint venture with China Foreign Exchange Trade System in Germany.
Chinese growth is slowing, with expansion falling to its lowest level since the global financial crisis in the third quarter.
Merkel said: "I definitely have confidence in the Chinese economy," adding that economic development undergoes "waves and changes".
Li said: "China's industry development level lags behind that of Germany. We need to learn advanced concepts and technology from Germany."