Abstract: A red phosphor where the crystal phase constituting the phosphor is monoclinic Eu-activated CaAlSiN3. A red phosphor which is Eu-activated CaAlSiN3 powder having an average particle diameter of 10 ?m or less as measured in the non-pulverized state by the laser scattering particle size distribution analysis. A light-emitting device comprising a blue light-emitting element, a yellow phosphor capable of converting the blue light emitted from the blue light-emitting element into yellow light, and the above-described red phosphor capable of converting the blue light emitted from the blue light-emitting element into red light. A method for producing Eu-activated CaAlSiN3, comprising firing a raw material powder comprising Ca3N2, AlN, Si3N4 and EuN at 1,400 to 2,000° C. in a nitrogen-containing atmosphere, the Ca3N2, AlN and Si3N4 giving a composition falling in the region surrounded by a straight line connecting the following four points A to D in the composition diagram of FIG.