The 20-year-old Ashford man was assaulted and verbally abused at a McDonald’s in Melrose Park early Tuesday morning.

The worker had handed the customer his food in the drive-through’s pick up bay when he was punched in the neck.

The man’s glasses broke in the assault, resulting in cuts to his face.

The 20-year-old was not hospitalised but was shaken.

“It’s a pretty savage attack on a worker who was just doing his job,” Shop, Distributive and Employees Association spokesman Jordan Mumford said.

“He’s a young worker and it’s not on for someone who’s just serving customers fast food to be subjected to this kind of thing.”

Police were called after the assault and CCTV footage was obtained.

Officers are investigating the incident and the suspect was not known to the victim, SA Police said.

The latest incident comes after a McDonald’s employee was assaulted in the Adelaide city centre in October.

That worker was spat on and verbally abused, with the alleged offender charged under new laws protecting retail staff.

Under the changes, people convicted of basic assault against a worker selling goods can face up to five years in jail while those convicted of assault causing harm can be imprisoned for seven years.

Mumford said the new laws sent a message it was unacceptable to assault a person at work.

“We want to see these tough new laws to be enforced for this particular instance,” he said.

“We want to get more awareness among the general public that this kind of behaviour towards frontline workers has serious consequences.”

Customer abuse increases over the festive period, with 85 per cent of union members reporting a rise in incidents.

“It’s completely ridiculous that people who are often giving up their public holidays, spending time with family and friends, to work in the service economy are subjected to this kind of abuse,” Mumford said.

-with AAP