Abstract: FeSiAl magnetic powder core was prepared from ball milling podwer followed by molding,and frequency propetties,and DC superposition characteristic of FeSiAl magnetic powder core has been studied.It was found that,at frequency of 1~500 kHz,effective permeability is constant,quality factor increasing with frequency increasing,but the quality factor decreases slowly after maximum level.At the same frequency,with decreasing the size of FeSiAl magnetic powder,the effective permeability decreases but the quality factor increases.FeSiAl magnetic powder core was possessed of good DC superposition characteristic,the percent permeability was less than 50% at DC bias field valued by 100 Oe,DC superposition characteristic was improved with decreasing the size of FeSiAl magnetic powder.