Long-haul business passengers will enjoy services comparable "with those available at powerful hotspots or upmarket hotels," Lufthansa boss Wolfgang Mayrhuber said in a statement.
"The service will gradually become available on all Lufthansa's long-haul flights worldwide," the firm said.
Spokesman Michael Lamberty said prototypes would be tested towards the end of this year, with the aim of rolling out the service on 50 long-haul planes in mid-2010.
Passengers will also be able to send text messages via mobile phone and transfer data via handheld communication devices like Blackberries or iPhones, he added.
While in-flight Internet is fairly common on domestic flights in the United States, it is still comparatively rare for airlines to offer the service on long-haul flights, Lamberty said.
Lufthansa withdrew a similar service at the end of 2006 after it failed to take off.