A method for manufacturing a powder magnetic core having Fe-M, M: Al or Cr, -based alloy particles bonded via an oxide phase in which the element M is concentrated, the method comprising: a first step of mixing a binder with a soft magnetic material powder containing Fe-M, M: Al or Cr, -based alloy particles on which an insulating layer is formed; a second step of filling a pressing die with a mixture obtained through the first step, subjecting the mixture to pressing to obtain a green compact, and slidingly demolding the green compact from the pressing die; a third step of processing the green compact after the second step and removing expansion deformed matter of the alloy particles present in a region where pressing flaws are formed on a surface of the green compact during the demolding, wherein a portion in which the alloy particles are scraped off and a portion having alloy particles falling off and being recessed from a processed surface are mixed in the processed surface; and a fourth step of subjecting the green compact after the third step to a heat treatment to oxidize surfaces of the Fe-M, M: A1 or Cr,-based alloy particles, so that the oxide phase is formed, wherein when the Fe-M-based alloy is an Fe-Al-based alloy, the Fe-Al-based alloy contains 4.0 % by mass or more and 14.0 % by mass or less of Al, when the Fe-M-based alloy is an Fe-Cr-based alloy, the Fe-Cr-based alloy contains 1.0 % by mass or more and 9.0 % by mass or less of Cr, when the Fe-M-based alloy is an Fe-Al-Cr-based alloy, in the Fe-Al-Cr - based alloy, a content of Al is 4.0 % by mass or more and 14.0 % by mass or less, Cr is contained in an amount of 16.5 % by mass or less in total of Cr with Al, and the content of A1 is greater than the content of Cr, and in any cases, an amount of Si is regulated to 5.0% by mass or less; an average particle size of the alloy particles of the soft magnetic material powder is 1 μm or more and 100 μm or less. a first step of mixing a binder with a soft magnetic material powder containing Fe-M, M: Al or Cr, -based alloy particles on which an insulating layer is formed; a second step of filling a pressing die with a mixture obtained through the first step, subjecting the mixture to pressing to obtain a green compact, and slidingly demolding the green compact from the pressing die; a third step of processing the green compact after the second step and removing expansion deformed matter of the alloy particles present in a region where pressing flaws are formed on a surface of the green compact during the demolding, wherein a portion in which the alloy particles are scraped off and a portion having alloy particles falling off and being recessed from a processed surface are mixed in the processed surface; and a fourth step of subjecting the green compact after the third step to a heat treatment to oxidize surfaces of the Fe-M, M: A1 or Cr,-based alloy particles, so that the oxide phase is formed, wherein when the Fe-M-based alloy is an Fe-Al-based alloy, the Fe-Al-based alloy contains 4.0 % by mass or more and 14.0 % by mass or less of Al, when the Fe-M-based alloy is an Fe-Cr-based alloy, the Fe-Cr-based alloy contains 1.0 % by mass or more and 9.0 % by mass or less of Cr, when the Fe-M-based alloy is an Fe-Al-Cr-based alloy, in the Fe-Al-Cr - based alloy, a content of Al is 4.0 % by mass or more and 14.0 % by mass or less, Cr is contained in an amount of 16.5 % by mass or less in total of Cr with Al, and the content of A1 is greater than the content of Cr, and in any cases, an amount of Si is regulated to 5.0% by mass or less; an average particle size of the alloy particles of the soft magnetic material powder is 1 μm or more and 100 μm or less.