Blue emitting phosphor SrZn₂(PO₄)₂:Eu²⁺ is synthesized by a high temperature solid state method, and the luminescent properties are investigated. At the 330 nm radiation excitation, SrZn₂(PO₄)₂:Eu²⁺ presents an emission band at 416 nm, which is assigned to the 4f⁶5d¹→4f⁷ transition of Eu²⁺ion. The concentration quenching effect of Eu²⁺in SrZn₂(PO₄)₂has been validated and proved to be a resonant type via a dipole-dipole interaction. The critical distance (R_c) of Eu²⁺in SrZn₂(PO₄)₂is calculated to be 3.244 nm. The Commission International de I’Eclairage (CIE) chromaticity coordinates of SrZn₂(PO₄)₂:Eu²⁺ locate at the blue region, such as (0.150, 0.072). The results indicate that the SrZn₂(PO₄)₂:Eu²⁺ phosphor may have potential applications in white light emitting diodes (LEDs).