The 41-year-old, who was found dead at her farm in Western Australia on Friday night, was one of Epstein's most outspoken accusers.
She became the face of a legal battle against the disgraced financier when she said Epstein sexually abused her and arranged for her to have sexual encounters with men, including Britain's Prince Andrew, starting when she was 17.
King Charles' younger brother strenuously denied her allegations and reached an out-of-court settlement with Ms Giuffre in 2022.
Her solicitor Karrie Louden confirmed on Saturday the mother-of-three had died at her property in the Neergabby area, about 80km north of Perth.
"We're all in shock," she told AAP.
"She was absolutely inspirational."
Ms Louden said she was initially contacted by Ms Giuffre's carer and went to the property to confirm the news.
"It was an honour to work with someone who was so strong and powerful and willing to advocate for victims of sexual abuse.
"It's a devastating loss to the community and survivors all over the world who saw her as an inspiration."
Ms Giuffre's family said "the toll of abuse" became too heavy for the sexual assault campaigner to handle.
"It is with utterly broken hearts that we announce that Virginia passed away last night at her farm in Western Australia," they said in a statement on Saturday.
"She lost her life to suicide after being a lifelong victim of sexual abuse and sex trafficking.
"In the end, the toll of abuse is so heavy that it became unbearable for Virginia to handle its weight."
Ms Giuffre alleged she had been groomed and sexually abused by Epstein and his associate and friend Ghislaine Maxwell since she was a teenager.
She alleged the pair trafficked her to the Duke of York when she was 17, a claim Prince Andrew has vehemently denied.
Her family described her as a "fierce warrior" in the fight against sexual abuse and sex trafficking.
"Despite all the adversity she faced in her life, she shone so bright ... she will be missed beyond measure," the statement said.
Ms Giuffre's long-time publicist Dini von Mueffling said her client was "one of the most extraordinary human beings I have ever had the honour to know".
"Deeply loving, wise and funny, she was a beacon to other survivors and victims," Ms von Mueffling said.
"It was the privilege of a lifetime to represent her."
WA police said they were called to a home in the Neergabby area on Friday night, where Ms Giuffre was found unresponsive.
"The death is being investigated by major crime detectives; early indication is the death is not suspicious," a statement from the force read.
Earlier in April, Ms Giuffre shared a photo on social media showing her face with what appeared to be extensive bruising, claiming she had just days to live after a school bus crashed into her car.
Lifeline 13 11 14
beyondblue 1300 22 4636
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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