Abstract: FeSiAl soft magnetic powder cores were made with warm compaction new technology of powder metallurgy.The influence of lubricant content, temperature and pressure of warm compaction on the density, permeability and magnetic loss of soft magnetic powder cores was researched.The result shows that the density and permeability increases, the magnetic loss decreases effectively after warm compaction.When adding 0.8wt%lubricant for warm compaction, 140 ℃and 700 MPa, the best magnetic properties are obtained.The permeability is 196.1(100 kHz) or 191.9(1000 kHz).The magnetic loss is 23.3 W/kg at 100 kHz,B_m=50 mT.