Till now, many doped persistent luminescence (PersL) phosphors have been invistigated and found various applications in such as bioimaging, photocatalysis and information storage, but introducing PersL emitters into a proper host is mostly complex. In this research, a self‐activated PersL phosphor Ba2Zr2Si3O12 (BZSO) is prepared by solid state reaction. By adding NH4Cl, the self‐activated PersL intensity is obviously enhanced. The trap depths and concentrations are examined by thermoluminescence spectra. Meanwhile, Bi3+ ions are introduced into BZSO and show wide band photoluminescence (PL) from 300 to 600 nm. Moreover, the PL of Bi3+ is tunable under excitation by 265‐350 nm lights. Furthermore, as a proof‐of‐concept design, we designed a patterned quick response (QR) code based on the self‐activated PersL of BZSO, and the information of “ South China University of Technology (SCUT)” can be read out by the code scanning technology. Bi3+‐doped BZSO phosphors are suggested to provide potential applications in information storage by its self‐activated PersL, and to excite researchers to study the tunable PL in Bi3+‐doped phosphor.