PbS　shares　several　similar　features　with　PbTe　and　PbSe,　and　it　is　much　more　earth-abundant　and　inexpensive,　which　is　characteristic　of　promising　Te/Se-free　thermoelectric　materials　for　intermediate　temperature　power　generation.　However,　its　thermal　conductivity　is　much　higher　than　those　of　PbTe　and　PbSe,　which　bring　a　big　challenge　for　obtaining　high-performance　PbS.　In　this　study,　we　rationally　integrate　multiscale　structure　involving　point　defects,　nanoprecipitates,　grain　boundaries　and　dislocations　in　PbS　by　doping　for　decreasing　lattice　thermal　conductivity　and　simultaneously　tuning　energy　band　configuration.　Density　functional　theory　(DFT)　calculations　demonstrate　that　the　ClS–SbPb　defects　with　the　lowest　formation　energy　create　an　obvious　shallow　donor　band　and　push　upward-moving　Fermi　level,　in　good　agreement　with　high　electrical　transport　properties.　Remarkably,　PbS-0.067%PbCl2-1.5%Sb　sample　presents　outstanding　ZT　of　~1.0　at　823　K　and　averaged　ZT　of　~0.62　at　423–823　K　due　to　a　low　lattice　thermal　conductivity　and　a　high　power　factor.　©　2020　Elsevier　Ltd