A car and truck collided at Merrick Road and Gale Avenue just after 1:45 a.m.
Police say Chelsi Perez, of Rockville Centre, was driving at a high rate of speed when she lost control on Merrick Road and collided with the box truck.
She was pronounced dead at the scene.
The 69-year-old driver of the box truck, who works for a church and was making a pickup, was evaluated at a nearby hospital for non-life threatening injuries.
Both vehicles were removed from the scene for brake and safety testing.
The investigation is ongoing.