The synthesis and photoluminescence mechanism of ZnGa2O4:Mn2+ are presented. Monitored at 450 nm, ZnGa2O4 exhibits an absorption band at 245 nm; monitored at 506 nm ZnGa2O4:Mn2+ exhibits absorption bands at 245 and 283 run. Under 254 nm excitation ZnGa2O4 exhibits a broad-band emission extending from 360 to 610 nn, peaking at 450 nm. This emission is gradually quenched, as a new band emerges, peaking at 506 nm, as Mn2+ is incorporated into the lattice (Zn1-xMnxGa2O4), where x = 0.006 at maximum intensity. Activator sensitization and host-to-activator energy transfer are suggested.