A phosphor ceramic having pores with a pore diameter of 3.0 μm or more and 12.0 μm or less, wherein in the phosphor ceramic, a pore volume percentage of pores with a pore diameter of3.0 μm or more and 12.0 μm or less is 1.5% by volume or more and 9.5% by volume or less, wherein the pore volume percentage of pores is determined by cutting the phosphor ceramic plate in the surface direction and its cross sectional surface in the surface direction is observed with a laser microscope, object lens 20 x, magnification 1800 for determining pore diameters; thereafter, cutting is further performed at an interval of 0.5 μm in the surface direction, and a total of 15 cross sectional surfaces over 7.5 μm in the thickness direction are observed; the pore diameter is obtained by using the maximum length of the pore observed among the 15 cross sectional surfaces; the pores are then sorted into pores with a pore diameter of less than 3.0 μm, which are identified as small pores, pores with a pore diameter of 3.0 μm or more and 12.0 μm or less, which are identified as middle pores, and a pore diameter of more than 12.0 μm, which are identified as large pores; and the pore volume is calculated based on sphericity, and a total volume of the sorted pores is calculated; the calculated total volume is then divided by the volume of the phosphor ceramic plate, which is the portion measured for the pore, including the pores, to obtain the pore volume percentage in the surface direction; the phosphor ceramic plate is then cut in the thickness direction, and the cross sectional surfaces in the thickness direction are observed for 15 surfaces in the same manner as described above, and the pore volume percentage in the thickness direction is determined in the above-described method; wherein the obtained pore volume percentage in the surface direction and the obtained pore volume percentage in the thickness direction are averaged to obtain the pore volume percentage of the phosphor ceramic plate. wherein in the phosphor ceramic, a pore volume percentage of pores with a pore diameter of3.0 μm or more and 12.0 μm or less is 1.5% by volume or more and 9.5% by volume or less, wherein the pore volume percentage of pores is determined by cutting the phosphor ceramic plate in the surface direction and its cross sectional surface in the surface direction is observed with a laser microscope, object lens 20 x, magnification 1800 for determining pore diameters; thereafter, cutting is further performed at an interval of 0.5 μm in the surface direction, and a total of 15 cross sectional surfaces over 7.5 μm in the thickness direction are observed; the pore diameter is obtained by using the maximum length of the pore observed among the 15 cross sectional surfaces; the pores are then sorted into pores with a pore diameter of less than 3.0 μm, which are identified as small pores, pores with a pore diameter of 3.0 μm or more and 12.0 μm or less, which are identified as middle pores, and a pore diameter of more than 12.0 μm, which are identified as large pores; and the pore volume is calculated based on sphericity, and a total volume of the sorted pores is calculated; the calculated total volume is then divided by the volume of the phosphor ceramic plate, which is the portion measured for the pore, including the pores, to obtain the pore volume percentage in the surface direction; the phosphor ceramic plate is then cut in the thickness direction, and the cross sectional surfaces in the thickness direction are observed for 15 surfaces in the same manner as described above, and the pore volume percentage in the thickness direction is determined in the above-described method; wherein the obtained pore volume percentage in the surface direction and the obtained pore volume percentage in the thickness direction are averaged to obtain the pore volume percentage of the phosphor ceramic plate.