Slimani, who won the French book world's top prize, the Goncourt, in November, was hailed as the French language's most popular author by the annual ranking run by French magazine L'Express in collaboration with RTL radio.
The book that stirred up all the fuss was a thriller, Chanson douce, a chilling tale of a "perfect" nanny who murders the two children she is looking after.
The book is to be made into a film soon.
Runners-up in the L'Express ranking were Petit pays by Gael Faye and La fille de Brooklyn by Guillaume Musso.
The list of 32 titles also includes books by politicians, including former president Nicolas Sarkozy's La France pour la vie (France for Life), former justice minister Christiane Taubira's Murmures à la jeunesse (Whispers to the Young) and hard-left presidential candidate Jean-Luc Mélenchon's L'avenir en commun (The Future Together).