Matthew Selby pleaded not guilty to the murder of his sister Amanda, 15, when he appeared at Mold Crown Court by videolink from HMP Berwyn on Friday.
She died after police were called to reports of a "domestic disturbance" at the Ty Mawr Holiday Park in Towyn, near Abergele, North Wales, on Saturday July 31.
Selby, of Ashton-under-Lyne, Greater Manchester, spoke only to confirm his name and enter his plea during the 10-minute hearing.
Judge Rhys Rowlands adjourned the case ahead of a trial on February 28, which is due to last up to seven days.
Following her death, Amanda's family released a statement through North Wales Police which said: "Amanda was a loving daughter and granddaughter - she was caring, thoughtful, liked to help others and very much loved. She will be very sadly missed."
Her school, Droylsden Academy in Greater Manchester, also paid tribute to her.
A message on its website said: "Our school family is devastated by this awful news. Amanda was a lovely student and she will be sorely missed by students and staff."