To provide a polarization module having strong environmental durability and an image display device.

A polarization module 100 includes a polarizer 1 and a plurality of first 1/4 wave plates 2 arranged on the polarizer 1 so that an optical axis is inclined at 45 degrees with respect to a polarization axis of the polarizer 1. The polarization module 100 further includes a plurality of second 1/4 wave plates 3 arranged on the polarizer 1 so that an optical axis is inclined at 45 degrees in the direction opposite to the optical axis of the first 1/4 wave plates 2. An image display device 300 comprises the polarization module 100 arranged on a display panel 10 having a first pixel region for displaying an image for a right eye and a second pixel region for displaying an image for a left eye.