Rodney Lee "Rod" Keele, 72, of Hamilton died after the ATV he was riding tipped over and he hit his head on the pavement.
Montana Highway Patrol Sgt. Scott Bennett said the man had pulled out of his driveway onto Long Lane when he apparently lost control and the ATV rolled onto its side.
Keele hit his head on the pavement. He was not wearing a helmet.
Bennett said Keele was pronounced dead at the scene.
The accident happened about midday Tuesday. Bennett said there was no indication that alcohol was involved.
Long Lane intersects with the Skalkaho Highway between mile markers 2 and 3.