Taking　into　account　of　the　temperature　dependence　of　emitter　junction　voltage,　the　valence-band　discontinuity　at　emitter　junction　(ΔE　v),　and　the　bandgap　narrowing　due　to　heavy　doping　(ΔE　g),　a　simple　method　to　optimize　the　ballasting　resistor　of　RF　power　heterojunction　bipolar　transistor　(HBT)　has　been　presented　based　on　the　thermal-electric　feedback　network　analysis.　The　agreement　between　theory　and　experiment　is　shown　to　be　excellent.　Using　this　design　flow,　we　can　choosing　the　best　ballasting　resistor　of　power　HBT　needed　for　thermal　stable　operation　under　the　specified　working　condition.