The Monet exhibit at the Grand Palais near the Champs-Elysee features extended hours to accommodate guests, Radio France Internationale reported.
The exhibition hall opened Friday morning and won't close until Monday evening. Ticket sales have exceeded 845,000 since the show opened Sept. 22.
"Queuing time can range from between 2 to 3 hours at around midnight but may be no more than 15 minutes at around three in the morning," the Grand Palais said in a statement.
Of the 65,000 people expected to attend the show this weekend, about 33,000 will visit during the nocturnal hours, officials said.
Officials said visitors could top 910,000. The last exhibit to draw that many people was the Egyptian King Tut exhibition in 1967.
Monet died in 1926 at age 86.