China Eastern Airlines and its subsidiary Shanghai Airlines have formally become members of the SkyTeam Alliance.
The addition of the Shanghai-based airlines gives SkyTeam 10% more daily departures to and from the Greater China region, says SkyTeam.
Guangzhou-based China Southern is already a member, while Taiwan's China Airlines is expected to join later this year.
China Eastern is the 14th airline to join SkyTeam, with the alliance expecting to have 19 members by 2012.