Teresa Yuan admitted guilt for harassing the Inception actress with a series of invasive emails and video messages.
Yuan, 32, apparently sent over 500 messages to Cotillard over just four days in 2011.
According to WENN, Yuan appeared at a Brooklyn Federal Court on Friday (September 28) to face the charges.
She now could serve up to 16 months in prison, although prosecutors have said they will not object to court-ordered psychological treatment.
Cotillard, who recently starred in Rust & Bone, has not commented publicly on the matter.