The pedestrian was hit by a vehicle on the Carlow to Castledermot road at approximately 7.20pm.
The 29 year old was pronounced dead at scene, and his body was taken to Waterford University Hospital where a post mortem examination is to be arranged.
The male driver of the vehicle was uninjured.
Gardai have closed the road to facilitate Forensic Collision Investigators and diversions are in place.
He's the second person to die on our roads on Christmas day – a teenage boy died when his motorcycle crashed into another bike on Cherry Orchard Avenue in Dublin.
Meanwhile, GSOC are investigating a separate collision yesterday between a Garda Patrol Car and a motorbike in the Summerhill area of Dublin, which has left a man in serious condition in Beaumont Hospital.
