Police said the ordeal was “extremely traumatic” for the teenager.
They appealed to the public for help to catch the attacker.
The girl was with friends in a wooded area behind a sports centre on Brediland Road, Linwood, about 9:45pm on Saturday.
As the group went their separate ways to go home, the 14-year-old returned to the woods to look for something she had lost.
She was then allegedly approached from behind by a man who sexually attacked her.
The man then fled the woods and the girl ran home to her mother, who contacted police.
The attacker, who was not known to the victim, is described as being in his early 20s with dark stubble. He was wearing a dark hooded top and dark trousers.
Detective Sergeant Alex Allardyce, from Paisley CID, said: “This was an extremely traumatic ordeal for the victim and specialist officers are currently working to establish the full circumstances surrounding what happened.
“I would appeal to anyone who was in the area near to the sports centre on Brediland Road around 9:45pm on Saturday and may have noticed a man matching the above description, or anything at all suspicious, to please get in touch.”