A University of Cincinnati Medical Centre spokeswoman confirmed the pupil's condition, about six hours after the shooting at the Catholic La Salle High School west of Cincinnati, Ohio.
She said his parents issued a statement thanking people for their thoughts and prayers, while asking for privacy.
She did not release any further information about the student's condition.
Police said there was no apparent threat to anyone else at the school.
The high school immediately went into lockdown, but students were then sent home.
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