The 29-year-old reportedly told a Las Vegas police lieutenant that she had borrowed the purse from a friend.
The heiress was arrested late Friday night in Las Vegas on felony possession of cocaine. She was released on her own recognizance, but faces a felony drug charge.
This is the third time this year that she's been accused of drug possession. Hilton was detained last month by authorities on a French island after allegedly being caught with less than one ounce of marijuana in her bag. She was arrested in South Africa during the World Cup on marijuana charges, but the charges were dropped.
On her Twitter account, Hilton tweeted, "I'm so thankful to all my fans for all the love and support you are giving me. Thank you all. Love you so much. Love Paris XOXO."