Train lines at Llanishen have re-opened after a fatality on the line around 8.30am this morning, but operators have warned of “severe” delays.
Bus services are currently supplementing the train service between Caerphilly and Cardiff Central.
Train services between Cardiff and Penarth have been delayed since the incident just before 8.20am.
A spokesman for Arriva Trains Wales said: “Services between Cardiff and Penarth are delayed or cancelled at short notice.”
“There are severe delays on the Valleys lines at the moment but we are hoping to resolve them as soon as possible.”
British Transport Police said they are treating the fatality as non-suspicious.
A British Transport Police spokesman said: “Officers were called to the line after a report that a man had been struck by a train.
“British Transport Police and South Wales Police officers attended the incident, which was reported at 8.17am and is currently being treated as
“Paramedics from the Welsh Ambulances Service NHS Trust also attended, but the man was pronounced dead at the scene.”
Enquiries are ongoing to establish the identity of the man and inform his family. A file will be prepared for the Coroner.
The line was handed back to Network Rail at 9.12am.
South Wales Police advised Station Road has been re-opened, but there is still congestion in the area.
A spokesman for Arriva Trains Wales said: “There are severe delays on the Valleys lines at the moment but we are hoping to resolve them as soon as possible.”