The man was among the planes when he was caught, wearing a warning vest that he had stolen and he also attempted to steal a baggage cart without succeeding.
The police are investigating how the man got into the protected area.
He has likely got in through the baggage handling system, says the police's press spokesperson Ola Österling.
The man is a Swedish citizen and is suspected of air traffic sabotage. The prosecutor has taken over the investigation.
Arlanda's security organization has functioned excellently, says Österling.
