The present invention relates to an underlayer for use in a high density magnetic recording media. More particularly, the invention relates to an underlayer for use in a high density magnetic recording media comprising A1Pd or CoTi intermetallic compound having B2 crystal structure, or Co50Ti50-xMxmetal alloy in which Ti in CoTi intermetallic compound is partly substituted by other substitutional elements while maintaining its B2 crystal structure, or CoTi/Cr of a double thin film structure in which a Cr seed layer is introduced. The underlayer provided by the present invention has a crystal structure and microstructure suitable for a high density magnetic recording media, which makes a good texture structure with a Co-based magnetic layer deposited thereon and shows fine grain size distribution, high coercity and high coercity squareness.