A plasma display panel 1 of the present invention has a protective film 14 over a sustaining electrode 15 and a scanning electrode 16, with the main components of the protective film being CaO and SrO, and the concentration of the CaO in the protective film 14 is 20 mol % or more and 90 mol % or less. This protective film 14 has a smaller work function than a conventional MgO film so light can be emitted at a lower discharge voltage than in the past. If the discharge voltage is lower, the protective film 14 will be sputtered more slowly so that the service life of the plasma display panel 1 will be longer. Also, since the plasma-gas contains xenon gas, the plasma display panel of the present invention has higher brightness.