Officers in Munich's Oktoberfest station met the star of Terminator and other Hollywood blockbusters after berating him for his dangerous actions.
Schwarzenegger told officers he was having trouble walking, and offered to pose for a picture as an apology.
Police tweeted that cycling was forbidden "even for the Terminator".
Two cyclists were seen racing through the station during a busy lunchtime period, the police said in a statement. One was stopped and warned about his conduct.
But the cyclist answered that he had to leave quickly because he was "the bodyguard of Arnold Schwarzenegger" before cycling off down a dead-end platform.
Thinking it was "a bad joke", officers waited for him to return - which he did, with Schwarzenegger in tow.
The star-struck officer "found his voice again", the statement said, and warned the pair that cycling at high speed was dangerous.
Police say the former governor of California - who was born in Austria and is a native German-speaker - admitted his mistake and apologised for his bodyguards.
Schwarzenegger is touring Europe promoting a series of sports festivals, and recently attended a training session at Barcelona football club.
Action star Arnold Schwarzenegger ran afoul of the German police for cycling through a busy train station - but got away with a selfie as his fine.