The delighted bride looked radiant in a strapless white gown, tied with a ribbon around the waist, for the ceremony which took place at St Joseph's church in the village of Miltown Malbay.
Among the guests sharing the couple's big day with them were U2 rocker Bono, his wife Ali Hewson and comedian Patrick Kielty.
Andrea, 35, chose her two sisters and bandmates Sharon and Caroline as her bridesmaids and brother Jim was also in attendance.
After the ceremony, the wedding party moved onto the nearby Doonbeg golf resort to continue celebrating the happy occasion.
The bride and her new husband began dating two years ago and got engaged last Christmas during a stay in Barbados.
Brett reportedly popped the question to the Corrs frontwoman with a £60,000 diamond ring at the five star Sandy Lane Hotel, owned by his father.