The incident happened outside a row of shops in Wandsworth Road just before 2.50pm yesterday (July 18).
Officers and London Ambulance Service crews attended and found a man who had been stabbed.
He was taken to hospital for treatment where his condition is unknown at this stage.
No arrests have been made as police enquiries continue.
A spokesperson for Metropolitan Police said: “Police were called at 2.48pm on Friday, July 18, to reports of a stabbing on Wandsworth Road, Battersea.
“Officers attended and found a male, in his 30s, with stab wounds.
“He was taken to hospital by paramedics where he is receiving treatment. Wandsworth Road has been closed in both directions and a crime scene is in place.
“There have been no arrests. This is believed to be an isolated incident and enquiries are ongoing.”
