Luminescence and defect properties of novel phosphor β-Zn3(PO4)2:Zr4+ were systematically investigated. Corresponding to its lowest optical absorption transition at 240 nm, phosphor emits a bluish-green light at 485 nm, which yields the Stokes shift about 20000 cm-1. The unusual optical properties of Zr4+ ion are ascribed to its uncommon coordination environment. In addition it shows intensive bluish-green long lasting phosphorescence(LLP) due to the existence of electron trap, which is generated by aliovalent substitution of Zr4+ ion for the cation site in the matrix as shown in thermoluminescence(TL) spectrum.