[Object] To provide in particular an Fe-based amorphous alloy powder which has a low glass transition temperature (Tg) and an excellent corrosion resistance and which is used for a dust core or a coil-embedded dust core, each having high magnetic characteristics. [Solution] An Fe-based amorphous alloy powder of the present invention has a composition represented by (Fe 100-a-bc-x-y-z-t Ni a Sn b Cr c P x C y B z Si t ) 100-± M ± . In this composition, 0 at%‰¤a‰¤10 at%, 0 at%‰¤b‰¤3 at%, 0 at%‰¤c‰¤6 at%, 6.8 at%‰¤x‰¤10.8 at%, 2.2 at%‰¤y‰¤9.8 at%, 0 at%‰¤z‰¤4.2 at%, and 0 at%‰¤t‰¤3.9 at% hold, a metal element M is at least one selected from the group consisting of Ti, Al, Mn, Zr, Hf, V, Nb, Ta, Mo, and W, and the addition amount ± of the metal element M satisfies 0.04 wt%‰¤±‰¤0.6 wt%. Accordingly, besides a decrease of Tg, an excellent corrosion resistance and high magnetic characteristics can be obtained.