Paris police said the loss amounted to "several million euros, mostly jewelry," adding that they were still assessing the total amount stolen and had opened an investigation.
A spokesperson for the celebrity had earlier described her as "badly shaken but physically unharmed" after the assault, which occurred late on Sunday.
The spokesperson said that "two armed masked men dressed as police officers" entered Kardashian's hotel room and held her up at gunpoint.
French police officers stand outside the scene of the robbery in Paris on Monday morning
The representative gave no further details, nor did the person say whether the incident was an attempted robbery or had another motive.
On hearing the news, Kardashian's husband, rapper Kanye West, abruptly ended a festival appearance in New York citing a "family emergency."
An hour into his set, West said mid-song, "I'm sorry, show's over," and quickly left.
12