Ward 4 at Ninewells Hospital is closed to new admissions due to a small number of patients who have flu.
Patients in the ward are being monitored and appropriate infection control measures are in place.
A NHS Tayside spokesperson said: “To help reduce the spread of infection, visitors are asked to avoid visiting if possible, but if they do they will be offered face masks, gloves and apron and asked to wash or gel their hands.
“We ask that visitors who have coughs and colds which could be flu not to visit friends and relatives until they are better.”
Dr Gabby Phillips, lead infection control doctor, said: “Ward 4 remains closed and we are closely monitoring the situation.
“Staff are adopting enhanced infection control precautions.”