Disclosed herein are a method and apparatus for normalizing the size of content in a multi-projection theater and a computer-readable recording medium. The method may include receiving theater parameters stored in a database, computing the scale factor of an image projected on a main screen based on the received theater parameters, controlling the image projected on the main screen by applying the computed scale factor to the image, and controlling the scale of an image projected on a sub-screen according to the controlled image of the main screen.