The present invention provides a compound powder for making magnetic powder cores, a kind of magnetic powder core, and a process for making them. Said compound powder is a mixture composing of powder A and powder B, the content of powder A is 50-96 wt. % and the content of powder B is 4-50 wt. %, wherein powder A is at least one selected from iron powder, Fe—Si powder, Fe—Si—Al powder, Fe-based nanocrystalline powder, Fe-based amorphous powder, Fe—Ni powder and Fe—Ni—Mo powder; powder B bears different requirement characteristics from powder A and is at least one selected from iron powder, Fe—Si powder, Fe—Si—Al powder, Fe-based nanocrystalline powder, Fe-based amorphous powder, Fe—Ni powder and Fe—Ni—Mo powder. Said powder B adopts Fe-based amorphous soft magnetic powder with good insulation property as insulating agent and thus core loss of magnetic powder core decreases. The decrease of magnetic permeability of magnetic powder core resulting from a traditional insulating agent is remedied and the initial magnetic permeability of magnetic powder core is improved by taking advantage of soft magnetic properties of Fe-based amorphous powder.