The 36-year-old was targeted by a gang of four men outside flats in Orchard Place, Masbrough, earlier this month.
CRIME: Men arrested over Sheffield murder remain in police custodyHis injuries were so severe he required surgery.
A photograph of the man's injuries has been released in a bid to encourage those with information to come forward.
A police spokeswoman said: "Police in Rotherham are appealing for information after a robbery and assault of a 36-year-old man earlier this month.
"At around 11.15pm on Saturday, March 3, the 36-year-old man was assaulted by a group of four men outside flats in Orchard Place, Rotherham.
"The men seriously assaulted the 36-year-old before running from the scene. One of the men is understood to have been armed with a baseball bat."
He added: "The 36-year-old suffered serious facial injuries, including broken upper and lower jaws that required surgery.
"The victim works as a takeaway delivery driver and was delivering an order in the area at the time of the robbery.
"Do you live locally? Did you hear or see anything suspicious?"
Anyone with information should call South Yorkshire Police on 101 quoting incident number 1,186 of March 3.
Crimestoppers can also be contacted anonymously on 0800 555 111