Idris Ahmed, 18, pleaded not guilty to causing grievous bodily harm with intent, inflicting grievous bodily harm, and possessing a knife on the beach.
During a hearing at Cardiff Crown Court on Friday, Judge Tracey Lloyd-Clarke, the Recorder of Cardiff, set a provisional trial date for November 2.
It is expected to last 10 days.
Ahmed, of Cardiff, spoke only to enter his pleas and nodded to confirm his name and date of birth.
Appearing in court in a grey prison tracksuit, he was remanded into custody.
Judge Lloyd-Clarke said: “Your trial date is fixed for November 2 of this year.
“You will be remanded in custody until that date.”
Peter Donnison, defending, said the teenager denies stabbing or encouraging anyone else to stab the alleged victim.
South Wales Police previously said a 17-year-old boy had suffered serious injury in the alleged incident at Barry Island on May 25.
