Michael Phelps was arrested for driving under the influence – SPLASH

Michael Phelps was arrested for driving under the influence in Baltimore, Maryland early this morning … TMZ Sports has learned.

The USA Olympic legend was pulled over around 1:40 AM in his white Land Rover, with almost twice the legal limit.

Officials issued a statement saying Phelps was initially pulled over for going 84 in a 45!

OUCH!