The 31-year-old Briton, who rides for Team Sky, posted a picture on Twitter of his damaged bike but said he was not hurt.
"Just got rammed on purpose by an impatient driver who followed me onto the pavement!" he wrote.
"Thankfully I'm okay. Bike totalled. Driver kept going!"
This year's Tour de France takes place from 1-23 July and Froome will be aiming to win the event for a fourth time and third in a row.
The incident follows the death of Italian cyclist Michele Scarponiafter he was involved in a collision with a van during a training ride in April.