Multi-finger　structure　is　commonly　used　in　microwave　power　GeSi　HBTs　(Heterojunction　Bipolar　Transistors).　Usually　equally　valued　emitter　ballasting　resistors　are　added　to　improve　thermal　stability　of　the　devices.　However,　self-heating　and　thermal　coupling　effects　make　the　temperature　distribution　on　emitter　fingers　non-uniform,　so　the　equally　valued　ballasting　resistors　structure　is　not　optimum.　In　this　paper,　an　unequally　valued　ballasting　resistors　structure　is　presented,　which　could　improve　the　uniformity　of　devices＇　temperature　distribution　effectively,　and　decrease　the　highest　temperature　to　a　certain　extent.