GaN-based　green　high-voltage　(HV)　light　emitting　diodes　(LEDs)　of　12　V　were　designed　and　fabricated.　The　optical　and　electrical　parameters　such　as　forward　voltage,　peak　of　wavelength,　optical　power,　and　luminous　efficiency　were　investigated　when　the　injection　current　varied　from　3　mA　to　50　mA　at　25°C.　The　results　show　that　the　injection　current　has　a　great　effect　on　the　optical　and　electrical　properties　of　the　GaN-based　high-voltage　LED.　When　the　current　is　20　mA,　the　corresponding　voltage　is　14　V.　With　the　increasing　of　the　injection　current,　the　blue-shift　of　LED　peak　wavelength　reaches　2　nm.　In　addition,　the　optical　power　increases　approximately　linearly　with　the　current　increasing.　The　luminous　efficiency　decreases　61%　when　the　injection　current　increases　from　3　mA　to　20　mA,　and　decreases　39%　when　the　injection　current　increases　from　20　mA　to　50　mA.　It　indicates　that　the　luminous　efficiency　decreases　more　slowly　when　the　high-voltage　LED　is　driven　by　large　current.　These　results　will　have　a　certain　reference　value　for　the　improvement　and　optimization　of　GaN-based　high-voltage　LEDs.