The teenager has been charged with the murder of 12-year-old Ava White in Liverpool city centre, police have said.
Merseyside Police said the girl was in town with friends after the Christmas lights were switched on on Thursday when she suffered a “catastrophic injury” in an attack at 8.39 p.m.
A 14-year-old boy, who could not be named for legal reasons, has now been charged with murder and possession of a bladed object.
Police said that he has been taken on remand to appear in court on Monday.
Three other boys, aged 13 to 15, were also arrested, who have been granted conditional bail as the interrogation continues.
Detective Superintendent Sue Combs said: “We are continuing to support Ava’s family and have requested that her privacy be respected during this difficult time.
“This is also important as we continue to investigate that no one posts comments or names on social media that could potentially affect us when we find justice for Ava’s family.
“Please trust us that we are doing everything possible to investigate and update people on this tragic incident, and we don’t want anything to jeopardize it.”
Ms Combs urged anyone in the aftermath of the incident to send pictures or footage to the force online at https://mipp.police.uk/operation/05MP21M43-PO1.