Police confirmed a man in his 40s was arrested on Thursday (August 21).
He has since been bailed pending further enquiries.
The incident happened in Deptford High Street just before 7.40pm on Wednesday (August 20).
Officers and London Ambulance Service crews attended and found a man who had been stabbed.
He was taken to a nearby hospital where his injuries were assessed as non-life threatening.
A spokesperson for Metropolitan Police said: “Police have launched an investigation into the circumstances.
“If you saw, or have any information about the incident, then please call 101 stating CAD6992/20Aug.
“To remain 100 percent anonymous, you can call the independent charity Crimestoppers on 0800 555 111 or visit crimestoppers-uk.org.
A spokesperson for London Ambulance Service said: “We were called at 7.35pm yesterday (20 August) to reports of a stabbing in Deptford High Road, Deptford.
“We sent an ambulance crew, paramedics in fast response cars and an incident response officer to the scene. We also dispatched a trauma team in a car from London’s Air Ambulance.
“We treated a patient at the scene and took him to a major trauma centre.”
