The disclosure discloses a display panel. The display panel includes an optical assembly, a blue-light OLED light source assembly, a red-light OLED light source assembly and a green-light OLED light source assembly, and the optical assembly includes a beam splitting prism. The blue-light OLED light source assembly, the red-light OLED light source assembly and the green-light OLED light source assembly are arranged at three sides of the beam splitting prism, respectively. And blue light emitted by the blue-light OLED light source assembly, red light emitted by the red-light OLED light source assembly and green light emitted by the green-light OLED light source assembly are emitted through the optical assembly. The disclosure also discloses a display device and a head-mounted display device.