Suffolk County police say 18-year-old Stanley Davis of Brentwood was fatally stabbed in the brawl early Saturday at the Commack Howard Johnson.
Police say several others were stabbed, including 20-year-old Jason Iglesias.
21-year-old Curtis Johnson sustained head injuries.
Police say one person was charged with obstruction of governmental administration when police arrived at the scene.
Another person was charged with disorderly conduct later at the hospital.
The investigation is continuing.
Detectives are asking anyone with information on the stabbing to call the Homicide Squad at 631-852-6392.