In　this　work,　the　variations　of　the　electrical　properties　and　trapping　effects　of　p-GaN　gate　high-electron-mobility　transistors　(HEMTs)　under　1-MeV　electron　irradiation　were　investigated　systematically.　When　the　irradiation　fluence　was　increased,　the　drain-source　current　and　the　gate　leakage　current　also　uprose,　but　the　threshold　voltage　shifted　toward　the　negative　direction.　Specifically,　after　final　irradiation,　traps　in　these　devices　were　identified　via　the　current-transient　method,　and　alteration　of　the　trapping　effects　near　the　drain　and　gate　could　be　observed,　respectively,　by　applying　different　filling　voltages.　According　to　the　time　constant　spectra　(TCS)　and　differential　amplitude　spectra　(DAS),　six　types　of　detrapping　behaviors　could　be　identified.　When　compared　with　the　results　during　the　pristine　stage,　the　absolute　amplitudes　of　the　traps　changed　after　irradiation,　which　indicated　trap　densities　decreased　near　the　drain　and　those　increased　near　the　gate.　The　observed　changes　in　the　trapping　behaviors　are　consistent　with　the　changes　in　the　electrical　properties.　To　identify　the　activation　energies　and　locations　of　traps,　the　current-transient　response　was　measured　at　various　temperatures　before　and　after　electron　irradiation.　The　possible　reason　for　the　increased　activation　energies　is　that　electron　irradiation　turned　the　Ga　vacancies　that　decorated　the　dislocations　into　pure　dislocations　and　increased　the　barrier　height.