A polarizer, a display panel and a display device including the polarizer are provided. The polarizer includes: a first polarizing layer, a first protective film and a first pressure-sensitive adhesive layer. The first polarizing layer includes a first hollow portion and a first polarizing portion surrounding the first hollow portion. The first protective film covers the first hollow portion and the first polarizing portion. The first pressure-sensitive adhesive layer is located at a side of the first polarizing layer facing away from the first protective film. With the display panel and the display device including the polarizer, since the first hollow portion is disposed in the first polarizing portion, an image collecting device such as a camera can be disposed in the polarizing region, thereby improving utilization of the surface area of the polarizer provided by the embodiments of the disclosure, and increasing the screen-to-body ratio.