Gallium oxide(Ga2O3),an ultra-wide bandgap semiconductor material,is attracting great interest for power devices,solar cells and ultraviolet detectors.The study of radiation damage effects is of importance for the application of Ga2O3 in harsh environment.In this work,it is the first time to observe the amorphous latent track of Ga2O3 single crystal by TEM.TEM images display that the mean diameters of amorphous latent tracks are 7.4,7.5 and 8.7 nm in Ga2O3 lamella samples irradiated by Ta ions with energy of 1786,1388 and 829 MeV,respectively.The latent track size meaured by TEM in this work is consisent with that measured by XRD in previous study[1].