The case has drawn criticism internationally, with Canada saying on Monday it would complain to the Saudi authorities about the sentence.
Josee Verner, Canada's minister responsible for the status of women, called the Saudi ruling "barbaric" and said it would only further violate the 19-year-old victim.
Verner said Canada would formally express its condemnation to "the appropriate Saudi authorities".
But the US, which wants Saudi Arabia to attend its Middle East conference in Annapolis next week, did not condemn the ruling.
Sean McCormack, a spokesman for the US state department, said: "This is a part of a judicial procedure overseas in the court of a sovereign country," when asked to comment on the case.
"That said, most would find this relatively astonishing that something like this happens."
Asked whether the Saudi authorities should reconsider the sentence against the woman, McCormack said he could not "get involved in specific court cases in Saudi Arabia dealing with its own citizens".
In October 2006, the woman was sentenced to 90 lashes for what the court called "illegal mingling".
According to Human Rights Watch, the woman said she had met a male friend who had promised to return a photograph of her.
|A Saudi woman can only have a husband or|
a male relative as an escort in public
After she met him in his car, the pair were attacked by a gang of seven men who allegedly raped them both several times.
The man was also sentenced to 90 lashes. Of the gang prosecuted in the case, four were convicted of kidnapping and sentenced to between one and five years in prison and between 80 and 1,000 lashes, Human Rights Watch said.
Abdul Rahman al-Lahem, the woman's lawyer and a human rights campaigner, criticised the court's decision publically and has subsequently had his licence to practise law suspended.
He is also facing a hearing by a justice ministry disciplinary committee in December for appearing regularly on television and talking about the case.
Farida Deif, researcher in the women's rights division of Human Rights Watch, said: "A courageous young woman faces lashing and prison for speaking out about her efforts to find justice.
"This verdict not only sends victims of sexual violence the message that they should not press charges, but in effect offers protection and impunity to the perpetrators."
The New York-based rights group has called on King Abdullah, the Saudi monarch, to cancel the ruling against the woman, drop all charges and order the court to end its harassment of her lawyer.