Rare　earth　zirconates　have　been　considered　as　promising　candidates　for　thermal　barrier　coatings,　with　extremely　low　thermal　conductivity　which　is　usually　attributed　to　their　unique　pyrochlore/fluorite　structure.　In　order　to　investigate　the　different　influence　of　pyrochlore　and　fluorite　structure　on　thermal　conductivity,　Gd2Zr2O7　ceramics　with　pyrochlore　and　fluorite　structure　were　prepared　separately　by　controlling　the　sintering　temperature,　and　the　thermal　conductivities　of　the　samples　sintered　at　different　temperatures　were　measured　and　investigated.　The　results　show　that　the　structure　of　Gd2Zr2O7　changes　gradually　from　pyrochlore　to　fluorite　as　the　sintering　temperature　increases　from　1450°C　to　1600°C,　accompanying　with　a　thermal　conductivity　decreasing　first　and　then　increasing.　The　minimum　value　of　thermal　conductivity　appears　on　the　sample　with　pyrochlore　structure　nearby　the　phase　transition　temperature　range,　rather　than　that　with　fluorite　structure.　Other　than　the　transition　of　structure,　structural　distortion　in　the　lattice　approaching　phase　transition　may　lead　to　a　distinct　decrease　of　thermal　conductivity.　©　Published　under　licence　by　IOP　Publishing　Ltd.