Adrian Bailey, 51, was taken from the Lunt-Fontanne Theatre shortly before 2 p.m. Saturday, the Fire Department said. The Broadway veteran was being treated at Bellevue Hospital Center.
Bailey is an ensemble member who plays various roles throughout the musical, show spokesman Chris Boneau said. The actor fell while preparing for the show's first scene, in which a boat is lowered to the stage, he said.
The Fire Department received a report that the actor fell 30 to 40 feet; Boneau said it was about 20 feet.
The audience was in the theater, but the curtain was down. The show had not begun and was delayed about an hour.
Bailey's previous Broadway credits include "La Cage aux Folles," "Smokey Joe's Cafe" and "The Who's Tommy."
The stage version of the 1989 Disney animated film "The Little Mermaid" opened at the theater in January. It tells the story of a sea maiden who longs to live on land.
Another Broadway musical, "Xanadu," postponed its opening briefly last year after one of its stars, James Carpinello, hurt his foot during a rehearsal.
