It has been detected in the Esplanade Hotel in Bray.
In a letter to asylum seekers in the centre today, the HSE says all residents will now be tested and they should restrict their movements.
Bulelani Mfaco, from the Movement of Asylum Seekers in Ireland, says the new cluster is a big concern.
"We have been concerned about clusters breaking out in direct provision centres across the country, since the beginning of this pandemic.
"What we are seeing is not actually going to change until the Government changes the living conditions of people in direct provision.
He said the people in the centre at the Esplanade Hotel in Bray are sharing intimate living spaces with other strangers who have their own lives.
Covid figures
This news come as two further deaths and 54 more confirmed cases of Covid-19 were recorded in the Republic yesterday by the National Public Health Emergency Team (NPHET).
The death toll now stands at 1,775 from a total of 27,547 cases.
Of the new cases, 67 per cent are aged under 45, and 27 are associated with outbreaks or are close contacts of a confirmed case.
Nineteen of the new cases were recorded in Dublin, eight in Kildare, five in Tipperary and the rest of the cases are in Carlow, Clare, Donegal, Kerry, Kilkenny, Laois, Limerick, Longford, Louth, Meath, Offaly, Waterford and Wexford.
