Anisotropic　bonded　NdFeB　permanent　magnets　have　wide　potential　applications　in　the　areas　such　as　brushless　DC　motors,　spindle　motors,　and　stepping　motors　due　to　their　excellent　processing　property　and　high　magnetic　properties.　Anisotropic　NdFeB　bonded　magnets　prepared　by　hydrogen-disproportionation-desorption-recombination　(HDDR)　process　have　large　energy　product　at　room　temperature.　However,　they　are　not　stable　at　similar　to　100　degrees　C,　which　is　the　working　temperature　of　many　electric　motors.　In　order　to　improve　their　thermal　stability,　we　developed　bonded　NdFeB/SmCo　magnets　and　investigated　the　effects　of　powder　particle　size　and　SmCo　content　on　their　magnetic　properties.　We　proposed　a　model　to　clarify　the　filling　effect　of　the　powder,　which　played　a　key　role　in　the　enhanced　(BH)(max)　when　reducing　the　SmCo　particle　size.　As　for　the　SmCo　content,　the　bonded　magnets　showed　improved　(BH)(max)　at　100　degrees　C-150　degrees　C　and　thermal　stability　with　the　increase　of　SmCo　content.　And　through　adjusting　the　SmCo　content,　the　remanence　temperature　coefficient　and　coercivity　temperature　coefficient　from　25-150　degrees　C　were　able　to　be　regulated　in　the　range　of　-0.14%/degrees　C　to　-0.04%/degrees　C　and　-0.51%/degrees　C　to　-0.14%/degrees　C,　respectively.　This　work　provides　a　design　strategy　and　a　facile　route　to　improve　the　magnetic　properties　and　thermal　stability　of　the　bonded　magnets.　(C)　2019　Author(s).