Abstract This report demonstrates an ultrawide bandgap β-Ga₂O₃ flash memory for the first time. The flash memory device realized on heteroepitaxial β-Ga₂O₃ film had TiN as the floating gate (FG) and Al₂O₃ as tunneling and gate oxides. A memory window of > 4 V was obtained between the programmed and erased states of the device. The memory states showed negligible degradation in threshold voltage (V_TH) even after 5000 s, exhibiting excellent nonvolatility. Furthermore, the device showed a V_TH of ∼0.3 V after applying a 17 V programming voltage pulse, indicating the potential of the electron trapping phenomenon in the FG to achieve enhancement-mode operation in β-Ga₂O₃ transistors for high-power and logic applications. This study would provide insights for future oxide electronics integrating β-Ga₂O₃ memory.