The　electronic　and　thermal　properties　of　hole　(Na)　and　electron　(Ga)　doped　CaMnO3　systems　are　investigated　based　on　the　first　principle　density　functional　theory　calculations　using　plane　wave　basis　and　pseudo-potential　method.　A　semiconductor-to-conductor　transition　and　a　distorted　band　structure　are　found　for　the　doped　systems;　enhanced　density　of　states　near　Fermi　level　is　observed.　The　phonon　transfer　speed　and　the　phonon　mean　free　path　are　lowered;　meanwhile,　the　phonon　specific　heat　is　heightened　in　comparison　with　that　of　the　undoped　CaMnO3　system,　resulting　in　enhanced　phonon　thermal　conduction.　The　calculation　results　indicate　that　the　doped　systems　should　have　improved　thermoelectric　performance.　(C)　2011　Elsevier　B.V.　All　rights　reserved.