Critical response
On the review aggregator website Rotten Tomatoes, 58% of 78 critics' reviews are positive, with an average rating of 5.50/10. The website's consensus reads: "An unforgettable blend of the conventional and the singularly strange, Aline is definitely odd, but it's also oddly entertaining." On Metacritic, the film has a weighted average score of 53 out of 100, based on 24 critics, indicating "mixed or average reviews". On AlloCiné, the film holds an average rating of 4.1/5 based on 35 press reviews.
Kyle Buchanan of The New York Times opined that Lemercier's decision to play the character throughout her life was the strangest aspect of the film:
"Shrunk to Hobbit size and Facetuned into near-oblivion, Lemercier scampers, preens and unnerves. I’ve never seen anything quite like it: Not PEN15, not John C. Reilly at the beginning of Walk Hard, not even a fully grown Martin Short playing a psychotic 10-year-old in Clifford. As a cinematic presence, Preteen Aline looks less like our main character and more like she’s ready to terrorize Vera Farmiga in the next Conjuring movie. Why didn’t they just cast an actual kid? I’m told that as a French comedian, Lemercier has often played children, but 'Aline' takes this shtick several steps too far: The movie is like Bohemian Rhapsody if they shrank Rami Malek and made him play his own teeth. Have you seen those Twitter prompts that ask you to reimagine a classic film with one character replaced by a Muppet? Aline reminded me of that, except the main character is the Muppet and instead of felt, she is made from your nightmares."
For Variety, Peter Debruge wrote that "Lemercier wouldn’t dare offend Dion, nor would she dream of giving fans the slightest reason to question their devotion, and so 'Aline' comes off feeling like a faith-based movie, where Dieu (French for 'God') gets the reverential 'lives of the saints' treatment. For those who adjust their expectations accordingly, it’s still an extremely satisfying watch — just one in which the only conflicts are convincing Aline’s parents to accept her love for manager Guy-Claude (Sylvain Marcel), the couple attempting to get pregnant and a tricky period when Aline’s vocal cords nearly give out. Suffice to say, most of the film’s tears are those of joy."
