A system for manufacturing an optical display device includes providing a roll of a belt-shaped sheet material including an optical film and a release film, which has score lines previously formed by cutting layers of the material other than the release film. The optical film is bonded to a rectangular optical display unit of the display device. In the bonding steps, a first optical film is divided by the score lines into pieces each having a length corresponding to a long side of the display unit, and a second optical film is divided by the score lines into pieces each having a length corresponding to a short side of the display unit. The first optical film has a first polarizing plate whose longitudinal direction is parallel to its absorption axis, and the second optical film has a second polarizing plate whose longitudinal direction is parallel to its absorption axis.