The crash happened close to Kilcullen.
A 41 year old Monaghan man was killed soon after midnight on Sunday night when his motorbike hit a ditch just outside Kilcullen.
Gardai have appealed for witnesses to the incident which occurred at approximately 12.45 on the R413 Brannockstown Road at Mile Mill.
The scene of the accident was sealed off until 1pm on Monday afternoon for forensic examination.
The deceased man, Clark Duffy, was no stranger to the area, Gardai say, and was on his way to a friend’s house where he was due to spend the night.
He was pronounced dead at the scene.
It is not, as yet known what happened. “It was a peaceful night,” a Garda source remarked.
And he called on anybody who may have seen anything in the area at the time to contact Naas Gardai on 045-884300.