The youngsters died after a crush near the Greenvale Hotel in Cookstown in Co Tyrone on Sunday evening.
The suspects, aged 52 and 40, are in police custody.
The Police Service of Northern Ireland said: “Detectives from PSNI major investigation team investigating the deaths of three teenagers at the Greenvale Hotel in Cookstown on Saint Patrick’s Day have arrested two men aged 52 and 40 earlier today, Tuesday 19 March, on suspicion of manslaughter.
“They are currently in custody.”
Tributes have been placed outside the hotel all day, and eyewitnesses have described scenes of chaos on the night of the deaths.