The victim was unhurt but his red and silver men’s mountain bike and grey iPhone 5s were taken after being threatened as he walked through Ruscote Park at around 4.30pm on Friday (December 21).
Investigating officer PC Liam Calvert based at Banbury police station, said: “This was a very distressing incident for this young boy who is now scared to leave the house.
“Anyone with information about this group of boys is asked to contact us to help with our investigation.
“You may have seen the offenders before or after this incident, so if you recognise the description of them or the stolen goods, please get in touch.”
The boy was walking near the shops when he was approached by five teenage boys who circled him and demanded he handed over his bicycle and phone, a police spokesman said.
The teenagers threatened to assault the victim so he handed them the bicycle and his phone.
The offenders walked away towards to alleyway in the direction of Banbury town centre.
All of the offenders are white boys, aged between 16 and 17 years old and of slim build.
Three of the offenders are described as being around 6 ft tall while the other two are around 5ft 5ins tall.
They were wearing black or grey Nike tracksuits with their hoods up and faces slightly covered. Some of the offenders had black Nike and Adidas bags.
Anyone with information should call the 24-hour Thames Valley Police enquiry centre on 101 quoting the reference 43180389339 or make a report online.
Or call the independent charity Crimestoppers anonymously on 0800 555 111.