In a video posted Thursday to YouTube.com, Paris Hilton apparently says she and her sister Nicky Hilton "are like two [N-word]" while they are dancing to Biggie Smalls' hip-hop song "Hypnotize."
In addition to the racial epithet, Hilton also appears to use a homophobic slur in the video, which is attributed to ParisExposed.com.
The hotel heiress has been accused in the past of using racial slurs, but has denied being a racist.
There is no indication of when or where the footage was taken, but it appears to be old.
Hilton filed a federal lawsuit Monday seeking to shut down ParisExposed.com, a Web site that displays personal photos, videos, diaries and other belongings once kept at a storage facility.
The Web site was launched last week claiming the items were auctioned off after Hilton neglected to pay the Los Angeles-area storage facility. It also promises visitors who pay a fee of $39.97 access to Hilton's passport, medical records and other legal documents.
In her lawsuit, Hilton said she put her possessions in storage two years ago when she and her sister Nicky moved out of a house that had been burglarized.
The 25-year-old heiress — who has gotten a reputation as a hard partier — said a moving company was supposed to pay the storage fees and was "shocked and surprised" to learn her belongings were sold at a public auction.
"I was appalled to learn that people are exploiting my and my sisters' private personal belongings for commercial gain," Hilton said in a declaration supporting the lawsuit, adding she was concerned the information could be used for identity theft or harassment.
The lawsuit alleges defendants Nabil and Nabila Haniss paid $2,775 for the contents of the storage unit and later sold the items for $10 million to entrepreneur Bardia Persa, who created the site.
Hilton's publicist Elliot Mintz said that she would like the site shut down and "would like all of these items returned to her."
Paris Hilton has gotten herself in trouble before. In the past, sex videotapes of her with a former boyfriend have circulated on the Internet.
The Associated Press contributed to this report.