A man in his late 40s is in hospital with serious injuries after his bicycle was hit by a bus in the Old Kent Road on Monday morning.
The collision between the bicycle and a 172 bus took place on the westbound carriageway near the Lidl store.
Police were called to the scene just after 9am and the road was partially closed for about three hours.
"A man in his late forties was taken to a central London hospital, where his condition is currently serious but stable," said a Southwark Police spokesman.
No-one has been arrested in connection with the collision.
Detectives from the serious collision investigation unit based at Catford are investigating.
Anyone who witnessed the collision is asked to contact police on 020 8285 1574.