A novel long persistent green emitting phosphor SrLaGaO₄: Tb³⁺ was synthesized via a conventional high temperature solid-state method. The obtained results indicated that the green long persistent emitting was similar to the photoluminescence, originating from the f -f transitions of Tb³⁺ centers which were supposed to occupy the random distribution Sr²⁺ and La³⁺ sites. The duration of green afterglow can be observed in the dark by naked eyes even after more than 3.5 h. The thermoluminescence results revealed that SrLaGaO₄: Tb³⁺ possessed three main traps calculated to be 0.62, 0.68 and 0.77 eV, which were responsible for the long persistent green luminescence. The further structure analysis revealed that the Tb³⁺ dopants not only acted as emission centers but also significantly influenced the density of traps, and the trapping centers were postulated nonrandom distribution under the assistance of high temperature, which resulted in the efficient persistent luminescence of Tb³⁺. All the results showed that SrLaGaO₄: Tb³⁺ was a potential long persistent luminescent material.