Channel　temperature　measurements　of　multi-finger　AlGaN/GaN　HEMTs　by　forward　Schottky　characteristics　are　presented.　The　temperature　dependence　of　the　forward　gate-source　Schottky　junction　voltage　is　investigated　and　it　is　used　as　the　temperature　sensitive　parameter　(TSP)　by　pulsed　switching　technique.　The　channel-to-mounting　thermal　resistance　of　the　tested　AlGaN/GaN　HEMT　sample　is　19.6　degrees　C/W.　Compared　with　both　the　measured　results　by　micro-Raman　method　and　simulated　results　of　a　three-dimensional　heat　conduction　model,　the　physical　meaning　of　the　channel　temperature　for　AlGaN/GaN　HEMT　tested　by　pulsed　switching　electrical　TSP　method　is　investigated　quantitatively　for　the　first　time.