A man died aboard an Irish Ferries vessel, Isle of Inishmore, when it was docked in Rosslare on Thursday.
The crew member, whose name has not yet been released, is understood to have died as the vessel was loading cargo.
Gardaí said the man in his 20s was fatally injured in an incident at 7.45am.
They said the coroner and the Health and Safety Authority were notified.
The Health and Safety Authority and the Garda have launched an investigation into the incident.
The 8.45am Rosslare to Pembroke and the 2.45pm Pembroke to Rosslare Ferries were cancelled as a result.
In a statement Irish Ferries confirmed it had been informed “by the company that provides its crew services” that “a very serious incident involving one of their crew members took place this morning on the Isle of Inishmore ship in the Port of Rosslare, while freight cargo was being loaded”.
“The incident is being attended by the emergency services. Our thoughts are with the family,” the statement said.
Crossings of the Isle of Inishmore resumed from Rosslare for Pembroke on Thursday evening at 8.45pm.