High　voltage　light　emitting　diodes　(HV-LEDs)　have　potential　advantages　on　general　lighting　application　for　their　special　features.　But　as　novel　power　LEDs,　their　optical,　electrical　and　thermal　characteristics　still　need　to　be　further　studied.　In　this　paper,　6　and　9　V　GaN-based　HV-LEDs　were　packaged　in　the　same　package　structure　and　process　conditions.　The　optical　characteristics　of　two　samples　were　investigated　under　different　temperatures　range　from　10　to　70　degrees　C　which　were　calibrated　to　junction　temperatures　using　thermal　impedance　measurement.　To　ensure　the　same　current　density,　working　current　was　set　to　150　mA　for　6　V　sample　and　100　mA　for　9　V　sample　respectively.　Results　show　that　the　increasing　junction　temperature　has　a　great　effect　on　EL　spectra　of　two　samples,　such　as　peak　wavelength　red-shifting,　full　width　at　half　maximum　(FWHM)　broadening,　luminous　efficiency　reducing　and　color　rendering　index　(CRT)　increasing.　The　junction　temperature　of　9V　sample　is　lower　than　that　of　6　V　sample　in　the　same　platform　temperature　and　injection　power.　With　temperature　increasing,　the　extended　quantitative　value　of　FWHM　for　9　V　sample　is　1.　3　nm　less　than　that　of　6　V　sample,　the　reduced　quantitative　value　of　luminous　efficiency　is　1.　13　lm　.　W-1　less　than　that　of　6　V　sample,　while　the　increased　quantitative　value　of　CRI　is　0.28　less　than　that　of　6　V　sample.　Those　data　suggest　that　EL　spectra　of　HV-LEDs　is　less　affected　by　junction　temperature　than　traditional　LEDs.　It　is　because　HV-LEDs　perform　better　in　current　spreading　and　generate　less　heat.　This　conclusion　has　reference　value　for　study,　development　and　applications　of　GaN-based　HV-LEDs.　In　addition,　peak　wavelength　still　has　a　good　linear　relationship　with　junction　temperature　and　it　can　be　a　temperature-sensitive　parameter　when　the　spectra　measurement　accuracy　is　enough.