Hanover Airport closed to flights for several hours on Saturday after a man drove a car through a fence onto the tarmac.
The incident happened around 15:40 local time (3.40am NZDT).
Hanover police said officials were able to stop the car, "overpower" the driver and take him into custody.
Flights in and out were suspended during their investigation, but resumed on Saturday evening after the man's vehicle was declared safe.
The incident came just over a week after German police announced they were tightening airport security over terrorism fears.
Police have said there was no indication that Saturday's incident was terror-related, and are reportedly investigating whether the man was under the influence of drugs.
The driver, who has not been named, is said to have driven through a perimeter fence onto the apron area of tarmac, where flights typically park and unload.
Images from the airport showed a vehicle and security response close to an Aegean Airlines aircraft.
The car is reported to have had Polish number plates, but no information about the man's nationality is known.
Inbound planes were diverted to nearby locations during the closure.
Police said flights resumed just after 20:00 (8am NZDT) after the vehicle was searched and no danger found.
Hanover Airport is located 11km (6 miles) from the city centre. Millions of people fly through it every year, but it is not considered one of Germany's major hubs.