Microcalorimetrywasdevelopedtodeterminethermalconductivities(λ)ofthermalinsulatorswithhollowcylindricalshapes,Aspecialdeviceofspecimentwithresistancethreadswrappedonitssurfaceandelectricheaterplacedinitsholewasdesignedtomeettheneedsofdeterminingλwithoutusingstandardsubstancestocalibratetheinstrument.Aformulaforcalculatingthevalueofλwasderived.Byheatingintheholeandonthesurfaceofthespecimenrespectively,thevaluesofλcanbeobtainedconvenientlybythistechnique.Themethodwastestedwithteflon,plexiglass,quartzglassandp[olyethylene.Theexperimentalvaluesofλforthefoursubstancesagreewellwiththeliteraturesones.Erroranalysiswasalsomadeontheexperimentaldata.Itwasfounrthatthemainfactorsaffectingvaluesofλare:(1)Theerroreofdeterminingthevaluesofheatcumulatedinspecimenandmaterialsinthespacearounditand(2)theerroreofdeterminingthevaluesofinnerandouterradiiofcylindricalspecimen.λ