The present invention discloses a display panel, a manufacturing method thereof and a display device. The display panel comprises a first substrate divided into a display area and a non-display area surrounding the display area, a plurality of sub-pixel units are provided on a part of the first substrate corresponding to the display area, a photo spacer is provided between two adjacent sub-pixel units and comprises a base and a plurality of protruding structures provided on the base, and the base is made from material including In+ ions which are replaceable with H+ ions. For the display panel, the photo spacers are manufactured using Haze phenomenon generated by contacting ITO thin film with ionized H2, so as to provide support between the encapsulation substrate and the evaporated substrate encapsulated by frit seal and effectively protect the OLED devices from damage, and therefore, the display panel has better performance.