The incident happened outside Bickley train station just before 3pm today (April 14).
Officers, including armed police, London Ambulance Service and an air ambulance were called to the scene.
The man was found injured and taken to hospital where his condition is currently unknown.
Two men have been arrested on suspicion of grievous bodily harm (GBH).
One of the men was also arrested on suspicion of possession of an offensive weapon.
The second man was further arrested on suspicion of possession of class B drugs.
A spokesperson for British Transport Police said: “Two men have been arrested following a stabbing outside Bickley railway station.
“Officers were called to the station just before 3pm today (Sunday 14 April) following reports of a man with a knife.
“The man is believed to be connected to reports of a stabbing on Southborough Road, close to the station.
“Officers, including armed officers, along with Metropolitan Police, London Ambulance Service and London’s Air Ambulance all attended the area.
“A man has been taken to hospital with injuries consistent with being stabbed.
“Two men have been arrested on suspicion of GBH. One of the men was also arrested on suspicion of possession of an offensive weapon.
“The second man, arrested by Metropolitan Police, was further arrested on suspicion of possession of drugs, class B.
“Enquiries into the circumstances are ongoing.
“Anyone with information is asked to contact British Transport Police on 61016 or 0800 405040 quoting reference 408 of 14/04/24.
“Alternatively, call Crimestoppers anonymously on 0800 555 111.”
