Officials at the Royal Cornwall Hospital have reopened all of its wards to visitors. About 10 wards were affected by the diarrhoea and vomiting bug.
That last closed ward was reopened on Friday after restrictions had been put in place in an attempt to control the Norwalk-type virus.
Visiting at St Michael's Hospital in Hayle and the West Cornwall Hospital in Penzance was allowed to return to normal on Thursday after outbreaks.