It happened last Tuesday at the Moorfoot junction with Shepherds, in Fullers Slade.
The victim, a 17-year-old boy, was walking in the area when three men got out of a white van, which was parked near Shepherds, and assaulted the boy.
They also made an attempt to get him into the van.
The victim managed to get away but sustained bruises and grazes during the assault.
The three men are black and were all wearing dark clothing.
Investigating officer Detective Constable Hollie Cromarty of Milton Keynes Force CID, said: “We understand this will be a concern in the community but we do believe this is an isolated incident.
“If anyone has information which could help with this investigation, we would ask that you come forward to the police.
“You can make a report via our non-emergency number 101, or online quoting the reference 43190330651.
