Horry County Coroner Robert Edge identified the girls as 16-year-old Daniela Alejandra Arriaza Flores and 17-year-old Amber Franco.
Myrtle Beach Police Lt. Joey Crosby said it happened just before 4 p.m. Wednesday. Officers found two bodies at the Camelot By the Sea Hotel. Flores fell to a 10th-floor parking deck. Franco's body was found on the roof of a ground-level Dunkin' Donuts. The hotel has 18 floors.
The cause of death for both teens was massive trauma from a fall, Edge said.
A spokesperson for Horry County Schools said the girls were students at Myrtle Beach High School, which is on spring break this week.
Harnett County Schools spokesperson Patricia Harmon-Lewis said Franco was a student at West Harnett High School for the 2015-2016 academic year and the school's four counselors are available for anyone who needs assistance.
Police are still investigating what led to the two girls' deaths. Crosby said authorities do not suspect foul play.
The Associated Press contributed to this report.