The Met said it was a planned arrest and not in response to any immediate danger but was part of an ongoing investigation into allegations of terrorist activities overseas.
The force added that the arrest was not related to Isis or Syria.
A residential address in north London is being searched by officers.
The arrested man is in police custody.
A 50-year-old man has been arrested on suspicion of a terror offence as he got off a plane at Heathrow Airport having flown in from Cairo.