LiNbO3 (LN) ferroelectric film was epitaxially grown on Ga-terminated AlGaN/GaN template with two dimensional electron gas (2DEG) in channel.The epitaxial relationship was [10-10]LNO//[1-2-10]GaN via30° in-plane rotation of the LNO film relative to the GaN layer.The results of piezoelectric force microscope showed that the LNO film had the preferable C+ oriented ferroelectric domains induced by the spontaneous polarization existing in the AlGaN and GaN layers.The capacitance-voltage characteristics were studied, and counterclockwise memory windows could be clearly observed.The size of the window was enlarged with increasing maximal applied bias (Vmax) and reached a maximum of 2.4 V when Vmax=4 V.This was attributed to the switchable ferroelectric polarization modulating on 2DEG.When Vmax exceeded 4 V, the window decreased due to the electron injection.In addition, a interesting phenomenon was found, enhancement-mode with off-state in LN/AlGaN/GaN HEMT was caused by LN ferroeleetrie polarization charges These results indicated that ferroeleetrie films combined with AlGaN/GaN would hold promise for next-generation GaN-based memory devices.