The incident happened just before noon at the R/C Reading Movies 11 & IMAX on North 2nd Street.
Authorities said the individual fell through the roof and plunged about 50 feet to the ground. The victim was pronounced dead at the scene.
The theater is currently undergoing renovations. Officials have not released information about the circumstances leading up to the fall or the identity of the person who died.
On its website, the theater announced it plans to reopen on Thursday.