Hard and corrosion resistance (Ti, Al)N film was deposited by pulsed high energy density plasma on the substrate of 045% C carbon steel at ambient temperature. The microstructure of the film has been investigated by SEM,XRD,XPS and AES. The nanohardness of the film was tested by nanoindentation tester. The corrosion resistance of the film was tested by potentiodynamic polarization in 05 mol /L H2SO4 aqueous solution. The results indicate that the film mainly composed of (Ti, Al)N and a small amount of AlN. The nanohardness of the film approaches 26 GPa. The corrosion resistance of the film is improved by about one order of magnitude, compared with 1Cr18Ni9Ti austenitic stainless steel.