Chromized coatings were fabricated using a conventional pack-cementation method. Effect of chromizing time, as well as natural ageing on the structure and performance was investigated. The phases and microstructure were characterized by scanning electron microscopy (SEM) with EDS and X-ray diffraction (XRD). The microhardness of the surface, the nanohardness of cross-section, the adhesion strength of the coatings were characterized by Vickers microhardness tester, nano-indenter and Rockwell-C tester. The results show that the chromized coatings were composed of Cr2N, (Cr,Fe)23C6 and (Cr,Fe)7C3. In the top surface, the discontinous Cr2N crystal grains distributed in the loose chromium carbides. The Cr2N crystal grains growth larger as the chromizing time increased. In the sublayer, the phase was composed of chromium carbides. The gradient structure was formed in the chromized coatings with Cr content decreased from surface to substrate and the contrary trend for Fe content. The microhardness of the surface was between 1492HV0.05~1698HV0.05 and it decreased slightly after 1 year natural ageing. The nanohardness reduced with Cr content decreasing in cross-section of chromized coatings. The Rockwell-C test results show that there were some radial cracks and spalls around the indentation crater. However, only radial cracks were presented around the indentation craters after 1 year natural ageing, indicated the improvement of adhesion strength of the coatings to substrate.