Police are appealing for witnesses following a robbery in Mcllroy Park, Tilehurst, last weekend.
The victim, aged in his 30s, was sitting with a friend when they were approached by three unknown men.
One of the males attempted to get the victim to stand up from his mobility scooter, before punching him several times with a small blade tucked between his fingers.
The victim, who was knocked unconscious, suffered a broken jaw, a deep cut under his eye, bruising to his body, and a black eye.
He was robbed of a gold necklace and around £60 in cash by the offenders, who also attempted to take his mobility scooter.
The suspects are described to be Asian men aged in their 30s.
The main offender was around five-foot-eight, clean shaven, of a stocky build, and was wearing a blue top and navy tracksuit bottoms.
The second is described as five-foot-11, wearing blue shorts and a white top, clean shaven and of a slim build.
The third was the same height as the second, wearing black shorts and a white top, clean shaven and of a slim build.
Investigating officer Detective Inspector Richard Jarvis, based at Reading police station, said: "This was a frightening experience for the victim, who is still experiencing difficulties with his vision following the incident.
"If you recognise the descriptions of these men, or have any other information about this incident, please get in touch."
Anyone with information is asked to contact police on 101, quoting reference 43200212472.
Alternatively, call Crimestoppers anonymously on 0800 555 111.