The special-needs student who went missing from her Brooklyn school on Monday has been found, cops said.

Nashaly Perez, 15, was last seen walking out of her high school, PS 371, around 1 p.m. on 37th Street near Fourth Avenue in Sunset Park, cops said.

“Certainly as a principal, and as a parent, and as a grandmother in particular, I am relieved to announce the child has been found and we are investigating the whole situation,” said Schools Chancellor Carmen Fariña.

Perez, who suffers from bipolar disorder, was found Thursday morning at a friend’s house in Brooklyn, according to police.

“I’ve been so worried. I couldn’t sleep since Monday. We never let her out by herself. She’s not allowed to go anywhere alone because of her condition,” said the teen’s mother, Sandra Rodriguez, who wept as she rushed out of her home to be reunited with her daughter.

Rodriguez blames the school for letting her daughter walk out during school hours and cited the case of Avonte Oquendo, another special-needs child who ran out of school Oct. 4, 2013, and was later found dead.

“The school was negligent in this case, not only did they allow her to walk out but they never notified or called me to let me know. It’s terrible what they did!” Rodriguez said.

Fariña said she doesn’t believe the cases are similar but an investigation is under way.

“We’re going to interview all the people involved. We’re going to see if protocols were followed. We’re going to see if protocols weren’t followed, who didn’t follow them. And then we will make a conclusion,” she said.

Perez was unharmed and appears to be in good health, law enforcement said.

Rodriguez said a prayer on the way to the precinct.

They were reunited at the 60th Precinct station house. Perez was taken to a local hospital for routine evaluation, sources said.

“I’m just glad she’s OK. I’m in shock,” said Rodriguez.

The principal of PS 371 has been reassigned pending the investigation.