In this paper

the near infrared persistent luminescent material ZnGa

2

O

4

：Cr

3+

is prepared by a high temperature solid state method and the photoluminescence

long persistent photoluminescence

photostimulated luminescence and thermoluminescence properties of ZnGa

2

O

4

：Cr

3+

are studied in details. The persistent luminescence excitation spectra reveal that the persistent luminescence of ZnGa

2

O

4

：Cr

3+

comes from the charge transfer transition from O

2-

to G

a

3+

instead of the intrinsic transition of Cr

3+

. The investigation in photo-stimulated persistent luminescence indicates that the sample can emit bright persistent luminescence again under infrared light excitation after the UV light excited persistent luminescence decays completely. The result shows that the UV light written information in ZnGa

2

O

4

：Cr

3+

can be read by infrared light. Moreover

in accordance with the result

the recombination luminescence model of conduction electrons is employed to elaborate the luminescence mechanism of the sample.