The West Ham United player wed the former reality star in a lavish ceremony, attracting a host of famous faces from the worlds of football and fashion.
O'Brien's teammate Andy Carroll was in attendance at the bash, which saw the pair marrying at St Augustin's Church on Thomas before celebrating their reception at Powerscourt Hotel with 200 guests.
And no expense was spared for their special day as the bride donned a custom-made Vera Wang white satin gown with mermaid detail.
The groom arrived just in time, with five minutes to go until the planned 2pm kick-off, but his bride made sure that her star player was left on tenterhooks, by arriving in style 20 minutes later in a silver Rolls Royce.
Joey then swept his bride away for a surprise helicopter ride from the Phoenix Park to the exclusive Powerscourt Hotel in Enniskerry, Co Wicklow, where they enjoyed a five-star reception.
There was a tight perimeter around the ceremony, with unofficial photographers and a number of onlookers being escorted down the street by members of security, who asked them to "move on" several times. Our photographer Conor McCabe was even threatened by one security guard. "He said I'd regret it if I stuck around," he said.