SrSiO3-3xN2x with a single chain inosilicate structure, which has not been realized in Sr and Sr-rich metasilicates, has been synthesized by introduction of a small amount of nitrogen into SrSiO3. Its crystal structure was determined by a single-crystal X-ray analysis. Anion sites are severely distorted along b-axis, resulting in formation of the inosilicate structure. The present material activated with Eu2+ exhibits red emission under near ultraviolet and visible light irradiation. Our results suggest a new strategy for development of novel oxynitrides.