Police are appealing for witnesses for information, after the incident happened at 11.45pm outside the Empire nightclub in Market Street.
The offender, a boy aged about 16 years old, approached the victim and stole his phone before running off towards McDonalds in Bracknell town centre.
He is described as mixed race, with a light moustache, 5 ft 8ins tall and of an athletic build, and he was wearing a dark puffer style jacket and dark tracksuit bottoms.
Three or four other men joined the offender while he was running off and they are described to be around 18 years old and wearing dark jackets with their hoods up.
One of the men is described to be around 5ft 7ins tall, of an average build with short dark blonde hair. He is thought to have had a ring through the right hand side of his bottom lip.
Any witnesses with any information should call 101 or Crimestoppers anonymously on 0800 555111.