Deshaun Watson found himself in trouble in Ohio just months after he was traded to the Browns ... TMZ Sports has learned he was busted for going 97 MPH in a 70 MPH zone in June.

The Ohio State Highway Patrol says it caught the star quarterback speeding in his G-Wagon in Sandusky -- less than three months after the Houston Texans dealt him to the Browns in a blockbuster trade.

Police body cam footage shows an officer pulled over the 27-year-old on June 11 ... and asked him if he had any clue how fast he was going.

"Like, 97?" said Watson, who also told the cop he had just been traded to the Browns.