The twin-engine business aircraft came down at lunchtime at a rubbish site near the western city of Trier.
The plane appeared to be a Cessna Citation business jet carrying two pilots and two passengers from England to an airfield at Foehren, near the crash site, police said.
A spokesman for Trier-Fohren airfield said the plane was travelling from Shoreham airport in West Sussex and all the deceased were German.
There was no immediate word on a possible cause for the crash. However, local sources suggest it hit a pylon in dense mist.