Shortly before 7 a.m., the woman, who is in her 20s, was running on the path near Highway 132 and Roland-Therrien Boulevard.
"A man came up on his bike, projected her to the ground and started to beat her," said Const. Mark David of the Longueuil Police.
The man then threw her down a 30-foot ravine, police said.
The victim fought him off and he fled on his bike in the direction of Marie-Victorin park.
A witness saw the injured woman and got help.
She was taken to the hospital with serious injuries to several parts of her body. Police said her life is not in danger and she was released from hospital this morning.
Longueuil Police set up a command post along the trail this morning hoping to find more witnesses to the attack or anyone with information on the suspect.
The suspect is described as a man in his 30s who is about five feet seven inches tall and weighs around 165 lbs.
He has short brown and gray hair and was wearing a blue and grey short-sleeved shirt, jeans and white running shoes. He left the scene on a dark-coloured mountain bike.
Anyone with information can contact the Longueuil police at 450-463-7211.