The red phosphor Y2Mo4O15:Eu3+ calcined at different temperatures is obtained by a solid‐state method, and is investigated in this article. Usage of solid‐state method with the combination of five different calcination temperatures (500, 550, 600, 650, and 700 °C) leads to the formation of pure monoclinic phase in all samples apart from the one calcined at the lowest temperature. Crystallite size obtained by Rietveld refinement is in the range of 38–55 nm. Scanning electron microscopy analysis confirms the presence of agglomerates. Luminescence emission spectra and emission decay curves are measured for all pure samples, and parameters derived from these measurements are used for Judd–Ofelt analysis. International commission on illumination (CIE) chromaticity diagram confirms the presence of pure red emission and high quantum efficiency.