The embodiments of the disclosure provide a display panel protective glass and a preparation method thereof, a display panel and a display device. The display panel protective glass comprises: a glass substrate; a white photoresist layer on the glass substrate, the white photoresist layer being arranged along a bezel region of the glass substrate; an isolation layer on the white photoresist layer; a black matrix layer on the isolation layer, the black matrix layer being arranged along the bezel region of the glass substrate.