Nikita Hand has been awarded €248,603 (£206,000) in damages after a jury at Dublin’s High Court found McGregor assaulted her in a Dublin hotel in 2018.
McGregor, 36, made no comment as he swiftly left court following the decision on Friday evening.
Speaking outside court after the decision, an emotional Ms Hand said the weeks of her civil case against the fighter have been a “nightmare”.
“I would like to start off by saying I’m overwhelmed and touched by the support I have received from everybody,” she said.
“I hope my story is a reminder that no matter how afraid you might be: Speak up, you have a voice and keep on fighting for justice.”
She said the civil case has not only impacted her life but her daughter’s, friends and loved ones.
Ms Hand continued: “It’s something that I’ll never forget for the rest of my life.
“Now that justice has been served, I can now try and move on and look forward to the future with my family and friends and daughter.”
McGregor previously told the court he had consensual sex with Ms Hand in a penthouse at the Beacon Hotel in December 2018.
Ms Hand told the court McGregor pinned her to a bed, choked her three times and “brutally raped and battered” her.
The civil court jury was told she was left with extensive injuries, including purple and blue bruising along her hands and wrists, a bloodied scratch to her breast and tenderness to her neck.
But lawyers for the fighter contested the lawsuit and accused her of attempted “extortion”.
They pointed to CCTV footage of Ms Hand arriving at and leaving the hotel with McGregor and a second man, James Lawrence, whom she also accused of sexual assault.
Both McGregor and Lawrence denied any wrongdoing. While she won her case against McGregor, Ms Hand lost her claim against Lawrence.
On Monday, McGregor’s legal team also told jurors it did not matter if they did not like or even loathed the famous fighter, urging them to look at the evidence and not his character.
McGregor and the claimant knew each other and had occasionally been in contact on social media, the civil trial heard.
Before the assault, Ms Hand had contacted the fighter, who picked up her and a friend in his car.
McGregor “came on to her”, but she did not want to have sexual intercourse with him as she was on her period, the trial heard.
