Abstract: This paper describes the method of the thermal analysis and optimization design for spacecraft heat pipe radiator.Two test samples of aluminium honeycomb heat pipe racliaror were built.In one of the samples the heat Pipes are inserted into the honeycomb panel facesheets and in the other the heat pipes are installed on the facesheet.Thermal performance of the two type radiators were evaluated by the tests and the theroretical calculation was proved.The design and solar simulation test of a heat pipe radiator for cooling TWTA of communication and Broadcating satellite are presented.