Magnetic metal particles containing iron as a main component, comprising cobalt in an amount of usually 20 to 50 atm%, calculated as Co, based on whole Fe, aluminum in an amount of usually 3 to 15 atm%, calculated as Al, based on whole Fe and a rare earth element in an amount of usually 3 to 20 atm%, calculated as rare earth element, based on whole Fe, and having an average major axis diameter of usually 0.02 to 0.065 µm, preferably from 0.02 to less than 0.05 µm, a coercive force of usually 159.2 to 222.9 kA/m (2,000 to 2,800 Oe), a soluble Na content of usually not more than 30 ppm, a soluble Ca content of usually not more than 100 ppm, and an oxidation stability Δσs of usually not more than 10%.