The　interfacial　thermal　resistance　between　two　solid　materials　is　usually　large,　but　there　is　still　no　way　to　eliminate　it　nor　uniform　measurement　standard.　Therefore,　in　thermal　measurement　technology,　because　the　surface　roughness　of　material　directly　affects　the　interface　morphology,　the　change　of　total　thermal　resistance　caused　by　the　thermal　contact　resistance　(TCR)　fluctuations　disturbs　the　accuracy　of　internal　thermal　analysis　of　the　device.　We　prepared　samples　with　different　surface　roughness　and　performed　thermal　measurements　on　them,　compared　with　the　test　under　vacuum　environment　and　the　condition　filled　with　thermal　interface　materials,　respectively.　We　found　the　heat　transfer　mechanism　at　the　fixed　interface.　More　importantly,　it　is　shown　that　in　the　interval　of　surface　roughness　Ra　©　2020　IEEE.