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PROBLEM TO BE SOLVED : To provide metal magnetic powder capable of obtaining a high density magnetic recording medium having satisfactory preservation stability and magnetic properties. SOLUTION : In the ferromagnetic metal powder composed of acicular grains of which : the content of the group Ia elements in the periodic table is reduced to ≤0.05 wt.%; further, the residual quantity of the group 2a elements in the periodic table made soluble is reduced to ≤0.1 wt.%; aluminum of 0.1 to 30 atomic% to the total quantity of the metallic elements and rare earth elements (including Y) of 0.1 to 10 atomic% to the total quantity of the metallic elements are comprised; powder pH is ≤10.1; and the length of the major axis is ≤0.12 μm.