A 10-year-old boy fled after a man tried to assault him after he refused to hand over a mobile phone.
The attempted robbery took place in Humphry Road, Sudbury, at around 5.15pm on Monday.
A man approached the boy and asked for his mobile phone. When he refused, the offender attempted to assault him.
The victim managed to run away and was not injured in the incident.
The offender is described as white, aged between 19 and 22, approximately 6ft 2in tall and of stocky build.
He had brown eyes, short black hair and was wearing a grey jumper, black tracksuit bottoms, black boots and had a black bandana covering his face.
He also had a two-inch scar beside his left eye.
Police are appealing for anyone who witnessed the incident or recognises the man to contact its priority crime team on 101, quoting SU/15/207.