Acting as the electron trap, oxygen vacancies can strongly influence the long persistent luminescence (LPL) properties were verified in Ca2Ga2GeO7: Zn2+ (CGGZ) phosphor. The existence of oxygen vacancies in this self-excitation material was confirmed by a simple fluorescence probe method. The introduction of zinc ions promotes the generation of oxygen vacancies, as well as optimizes its LPL properties. Thermoluminescence (TL) analysis revealed that electrons in deep trap will effectively transfer to the shallow one via the bridge of interstitial zinc. Accordingly, a mechanism for PL and LPL in this Gallogermanates was provided.